catalog: ace-step v5 — defaults audit against upstream Gradio UI

asset_engine consumer audited the entire ace-step entry's defaults
and slider ranges against acestep/ui/components.py (althing thread
01KRCN0SHP9YJGQD58EE95DC5P). The catalog had been authored from
documentation rather than from source; ten defaults were wrong and
several slider ranges were either too narrow or impractically wide.

Defaults changed (catalog -> upstream-authoritative):
  infer_step                 20    -> 60
  guidance_scale             7.5   -> 15.0
  cfg_type                   cfg   -> apg
  omega_scale                0.5   -> 10.0
  guidance_interval          0.0   -> 0.5
  guidance_interval_decay    1.0   -> 0.0
  min_guidance_scale         1.0   -> 3.0
  use_erg_tag                false -> true
  use_erg_diffusion          false -> true
  actual_seeds               [42]  -> []   (random per call)

Slider ranges adopted from upstream where reasonable; bounded
locally where upstream's range is so wide it's unusable as a UI
slider:
  guidance_scale         [1.0, 15.0]   -> [0.0, 30.0]   (upstream)
  guidance_scale_text    [0.0, 15.0]   -> [0.0, 10.0]   (upstream)
  guidance_scale_lyric   [0.0, 15.0]   -> [0.0, 10.0]   (upstream)
  lora_weight            [0.0, 2.0]    -> [-3.0, 3.0]   (upstream)
  audio_duration         [5.0, 600.0]  -> [5.0, 240.0]  (upstream max)
  omega_scale            [0.0, 1.0]    -> [-10.0, 30.0] (UI bound; upstream is [-100, 100])
  min_guidance_scale     [0.0, 10.0]   -> [0.0, 20.0]   (UI bound; upstream is [0, 200])

Verified empty-string actual_seeds path against the live pipeline
source: pipeline_ace_step.py:set_seeds() falls through to
torch.randint when manual_seeds is "" (string, no comma, not all
digits). Smoked end-to-end: HTTP 200 in 11s, real WAV bytes back.

Reproducibility gap honestly documented in the entry's
reproducibility.notes and the actual_seeds field description: with
the new default `actual_seeds: []`, the wrapper rolls a random seed
inside the pipeline but doesn't capture or surface the chosen seed
back through the response. Default-defaulted assets cannot be
regenerated bit-exact; users requiring reproducibility must set
actual_seeds explicitly. Wrapper enhancement to surface the chosen
seed via X-Actual-Seeds header + a CatalogResponse.header_accessories
schema field is the planned fix.

ace-step bumped version 4 -> 5. catalog_version stays at 1 (no
schema changes).

Also added a "source-of-truth precedence" subsection to
CATALOG-CONTRACT.md's service-authoring notes, codifying the
read-order (Pydantic model > handler/pipeline code > Gradio UI >
README). Three ace-step bugs in three rounds (missing field, wrong
enums, stranded bytes, wrong defaults — really four) all share the
same root cause: catalog authored from doc surfaces that lie by
omission.

docs/asset-engine/services.yaml

@@ -752,7 +752,7 @@ services:
       Apache-2.0 hybrid diffusion+LLM music generation. Multi-minute lyric-aware
       songs with vocals + instrumentation.
     category: music
-    version: 4
+    version: 5
     host: irv-ml1
     endpoint: http://10.100.79.3:8210/generate
     method: POST
@@ -800,20 +800,29 @@ services:
       - name: audio_duration
         type: slider
         min: 5.0
-        max: 600.0
+        max: 240.0
         default: 30.0
         label: Duration (seconds)
         section: basic
+        description: >
+          Upstream caps at 240s (the model's training horizon). Lower bound
+          5s is our choice — upstream uses -1 as a "random duration" sentinel
+          which is hostile UX for a slider. Default 30s also kept (upstream
+          uses -1; explicit 30 is the better first-time-user experience).
       - name: infer_step
         type: number
-        default: 20
+        default: 60
         label: Inference Steps
         section: generation
+        description: >
+          Upstream Gradio default is 60 (matches benchmark numbers in the
+          README). Lower values (20-30) are useful for "preview" passes;
+          higher (80-100) marginal returns.
       - name: guidance_scale
         type: slider
-        min: 1.0
-        max: 15.0
-        default: 7.5
+        min: 0.0
+        max: 30.0
+        default: 15.0
         section: generation
       - name: scheduler_type
         type: select
@@ -827,44 +836,67 @@ services:
       - name: cfg_type
         type: select
         options: [apg, cfg, cfg_star]
-        default: cfg
+        default: apg
         section: generation
         description: >
-          Classifier-free guidance variant. `cfg` is the standard formulation;
-          `apg` (adaptive projected guidance) and `cfg_star` are advanced
-          alternatives — see the upstream pipeline source for trade-offs.
+          Classifier-free guidance variant. Upstream Gradio default is `apg`
+          (adaptive projected guidance); `cfg` is the standard SD-style
+          formulation; `cfg_star` is an advanced alternative. See the
+          upstream pipeline source for trade-offs.
       - name: omega_scale
         type: slider
-        min: 0.0
-        max: 1.0
-        default: 0.5
+        min: -10.0
+        max: 30.0
+        default: 10.0
         section: generation
+        description: >
+          Upstream technically allows [-100, 100] but values that wide are
+          unusable as a slider. UI-bounded to [-10, 30] which covers the
+          typical zone with headroom. Hit the API directly for extremes.
       - name: actual_seeds
         type: json
-        label: Seeds
-        default: [42]
+        label: Seeds (empty = random)
+        default: []
         section: generation
+        description: >
+          Empty list = wrapper sends empty string to pipeline = pipeline
+          picks a random seed per batch element. Explicit seeds (e.g. [42]
+          or [42, 137, 9999]) for reproducibility.
+
+          REPRODUCIBILITY GAP (queued for follow-up): the pipeline returns
+          the chosen seed in its result dict, but our wrapper currently
+          throws it away. Assets generated with the default `[]` cannot
+          currently be regenerated. Workaround: set actual_seeds explicitly
+          when reproducibility matters. Wrapper enhancement to surface
+          random-resolved seeds via X-Actual-Seeds header + a catalog
+          schema field for header→accessory capture is the planned fix.
       - name: guidance_interval
         type: slider
         min: 0.0
         max: 1.0
-        default: 0.0
+        default: 0.5
         section: conditioning
       - name: guidance_interval_decay
         type: slider
         min: 0.0
         max: 1.0
-        default: 1.0
+        default: 0.0
         section: conditioning
+        description: >
+          Upstream Gradio default is 0.0 (no decay). Catalog v4 had this at
+          1.0 (full decay) — wrong; produced under-conditioned outputs.
       - name: min_guidance_scale
         type: slider
         min: 0.0
-        max: 10.0
-        default: 1.0
+        max: 20.0
+        default: 3.0
         section: conditioning
+        description: >
+          Upstream technically allows up to 200; UI-bounded to 20 (covers
+          the typical zone). Hit the API directly for extremes.
       - name: use_erg_tag
         type: bool
-        default: false
+        default: true
         section: conditioning
       - name: use_erg_lyric
         type: bool
@@ -872,7 +904,7 @@ services:
         section: conditioning
       - name: use_erg_diffusion
         type: bool
-        default: false
+        default: true
         section: conditioning
       - name: oss_steps
         type: json
@@ -881,13 +913,13 @@ services:
       - name: guidance_scale_text
         type: slider
         min: 0.0
-        max: 15.0
+        max: 10.0
         default: 0.0
         section: conditioning
       - name: guidance_scale_lyric
         type: slider
         min: 0.0
-        max: 15.0
+        max: 10.0
         default: 0.0
         section: conditioning
       - name: audio2audio_enable
@@ -912,10 +944,13 @@ services:
         section: lora
       - name: lora_weight
         type: slider
-        min: 0.0
-        max: 2.0
+        min: -3.0
+        max: 3.0
         default: 1.0
         section: lora
+        description: >
+          Negative weights are legitimate (apply the LoRA in inverse).
+          Upstream Gradio range adopted verbatim.
       - name: audio_format
         type: select
         options: [wav, mp3, flac]
@@ -961,10 +996,18 @@ services:
       notes: >
         actual_seeds parameter exposed; identical seeds + params = identical audio.
         Local infer-api.py patches upstream's broken 24-arg pipeline signature
-        (was 18 in upstream — caused crashes with audio_duration in `format` slot)
-        AND inline-streams the generated audio bytes (was returning a JSON
-        path reference to a file inside the container, which was unreachable
-        from outside).
+        (v2: was 18 in upstream — caused crashes with audio_duration in `format`
+        slot) AND inline-streams the generated audio bytes (v4: was returning a
+        JSON path reference to a file inside the container, which was
+        unreachable from outside).
+
+        REPRODUCIBILITY GAP (v5): default `actual_seeds: []` triggers random
+        seed selection inside the pipeline. The chosen seed IS available in
+        the pipeline's return dict (`actual_seeds` key) but our wrapper
+        doesn't capture or surface it — so default-defaulted assets cannot be
+        regenerated bit-exact. Set actual_seeds explicitly when reproducibility
+        is required. Wrapper enhancement to surface chosen seeds via response
+        header + a catalog schema for header→accessory capture is queued.
     estimated_latency:
       cold_start_s: 30
       warm_per_unit: "~10–60s depending on audio_duration + infer_step"