docs(workspace-runtime): migrate github.com refs at source so mirror inherits Gitea links (internal#41)

The molecule-ai-workspace-runtime mirror is regenerated on every
runtime-v* tag from this monorepo's workspace/. Per saved memory
reference_runtime_repo_is_mirror_only, mirror-guard rejects direct
PRs to the mirror; edit at source.

Source-side files that propagate to the mirror's published README +
read by users of the in-monorepo workspace-runtime docs:

- scripts/build_runtime_package.py (the README generator):
  * line 281 README_TEMPLATE: 'Shared workspace runtime for Molecule
    AI' link → Gitea
  * line 399 doc-link to workspace-runtime-package.md → Gitea path
    (with /src/branch/main/ shape)
  LEFT AS-IS (per Q3 audit-trail decision):
  * lines 379, 392 historical issue cross-refs (#2936, #2937)

- workspace/build-all.sh:5 — comment block linking to template-*
  repos. Migrated to Gitea path-shape.

- docs/workspace-runtime-package.md:
  * lines 101-108 adapter→repo table (8 templates, all PUBLIC on
    Gitea) — Gitea URLs
  * line 247 starter-repo link — substituted host + added inline
    note that starter doesn't survive the suspension migration
    (recreation pending; cross-link to this issue)
  * line 259 generic git clone command for new templates → Gitea
  * line 289 second starter mention — same handling as 247

Files NOT touched in this PR:
- workspace/ Python source code (.py files) — those use github
  paths in docstrings + a few log strings; fix bundled with the
  cross-repo Go-module-style migration (per #37 Q5 + parked
  follow-ups).
- 'Writing a new adapter' section's `gh repo create` command (line
  254-256) — gh CLI doesn't talk to Gitea (per #45 parked follow-up).
- 'Writing a new adapter' section's ghcr.io image ref (line 276) —
  per #46 ghcr→ECR migration (separate concern).

After this PR merges to staging + a runtime-v* tag is pushed, the
mirror's published README will inherit the Gitea link. Until then
the mirror's README continues to reference github.com/Molecule-AI
(stale but historical-marker-correct since the mirror existed
pre-suspension).

Refs: molecule-ai/internal#41, molecule-ai/internal#37,
molecule-ai/internal#38, molecule-ai/internal#42,
molecule-ai/internal#45, molecule-ai/internal#46

scripts/build_runtime_package.py

@@ -278,7 +278,7 @@ include = ["molecule_runtime*"]
 README_TEMPLATE = """\
 # molecule-ai-workspace-runtime
 
-Shared workspace runtime for [Molecule AI](https://github.com/Molecule-AI/molecule-core)
+Shared workspace runtime for [Molecule AI](https://git.moleculesai.app/molecule-ai/molecule-core)
 agent adapters. Installed by every workspace template image
 (`workspace-template-claude-code`, `-langgraph`, `-hermes`, etc.) to provide
 A2A delegation, heartbeat, memory, plugin loading, and skill management.
@@ -396,7 +396,7 @@ If you don't need real-time push, the default poll path works
 universally with no extra setup; both modes converge on the same
 `inbox_pop` ack so messages never duplicate.
 
-See [`docs/workspace-runtime-package.md`](https://github.com/Molecule-AI/molecule-core/blob/main/docs/workspace-runtime-package.md)
+See [`docs/workspace-runtime-package.md`](https://git.moleculesai.app/molecule-ai/molecule-core/src/branch/main/docs/workspace-runtime-package.md)
 for the publish flow and architecture.
 """