claude: point SemVer etiquette at canonical VERSIONING-POLICY.md

Global versioning questions now resolve against
corviduo-project-template/docs/VERSIONING-POLICY.md (self-pinned
versioning-policy-v1); the SemVer etiquette section is declared as
the Corviduo cadence layer on top — it wins on cadence/tier choice,
the policy wins on format, contract semantics, pre-release staging,
and release mechanics.

home_root/.claude/CLAUDE.md

@@ -374,6 +374,26 @@ Specifically, never append:
 
 ## SemVer etiquette
 
+**Canonical policy reference:** the formal versioning policy for ALL
+projects lives at
+`~/development/corviduo-project-template/docs/VERSIONING-POLICY.md`
+(canonical, self-pinned as `versioning-policy-v1`). It governs version
+format (SemVer 2.0.0), the public-contract declaration each project
+must make, pre-1.0 semantics, pre-release staging (`-alpha.N` /
+`-beta.N` / `-rc.N`, the same-commit rc discipline), dev/in-progress
+labeling per ecosystem, commit conventions, the release process, and
+special cases (hotfix, deprecation, breaking security fix, build
+metadata). Consult it for any versioning question this section doesn't
+answer — especially pre-releases and release staging, which this
+section doesn't cover.
+
+This section is Corviduo's **operational cadence layer on top of that
+policy**: which commits become releases and at what tier (tier-bar
+test, patch-default, operator approval for non-patch). Where the two
+differ on cadence or tier choice, this section governs; for format,
+contract semantics, pre-release staging, and release mechanics, the
+policy governs.
+
 Each code-bearing or substantive-artifact commit bumps a version in
 the project's `pyproject.toml` (or equivalent), refreshes the
 lockfile, gets a `vX.Y.Z` git tag. Establishes a fine-grained