Unified the fallback default for PLATFORM_URL from `http://platform:8080`
(Docker Compose service name) to `http://host.docker.internal:8080`
across all 13 modules that declare it. This matches:
- The provisioner's default (buildContainerEnv injects PLATFORM_URL
from cfg.PlatformURL, which defaults to host.docker.internal on the
platform side — main.go:platformURL)
- The molecule-git-token-helper.sh script (already uses host.docker.internal)
- The MCP client (MOLECULE_URL injected by provisioner)
The provisioner always sets PLATFORM_URL in production containers, so
this is a development/Docker-only improvement: without this change,
a workspace started outside the Docker Compose network (e.g. via
`docker run` with `--network host`) would fail platform API calls
with "Connection refused" because `platform:8080` resolves nowhere.
13 modules updated: a2a_cli, a2a_client, a2a_mcp_server, adapters/base,
builtin_tools/a2a_tools, builtin_tools/approval, builtin_tools/delegation,
builtin_tools/hitl, builtin_tools/memory, consolidation, coordinator,
main, molecule_ai_status. All docstrings updated to match.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>