Consume shared GitHub mount-path parser instead of hand-rolled regexes

[miyaontherelay]

Problem

Factory currently parses GitHub Relayfile mount paths with local regexes in src/orchestrator/factory.ts. This already drifted once: PR ingestion handled compact repo paths like OWNER__REPO, while issue ingestion only handled split OWNER/REPO paths.

The short-term bug is fixed in PR #20 by updating the local issue regexes, but the robust long-term fix is to consume a shared parser from relayfile-adapters once it exists.

Desired robust fix

After AgentWorkforce/relayfile-adapters#224 exports a GitHub mount-path parser, replace factory local parsing logic with that shared contract:

• githubIssuePathParts() should delegate to the shared issue parser.
• githubPullPathParts() should delegate to the shared PR parser.
• githubIssueDirectoryPathParts() and tree-path checks should use shared parser support for directory-event paths, or a shared repo-path parser plus resource-specific parser.
• Keep factory-specific filtering and routing logic local; only path-shape knowledge should move out.

Acceptance criteria

• Factory no longer duplicates split-vs-compact GitHub repo parsing in multiple regexes.
• Existing regressions from PR Handle compact GitHub issue repo paths #20 still pass: split OWNER/REPO, compact OWNER__REPO, by-id, flat JSON, nested meta.json, nested metadata.json, and directory events.
• PR path behavior remains unchanged.
• Add or keep contract tests based on fixtures from relayfile-adapters.

Related

• Immediate bug: GitHub issue ingestion misses owner__repo relayfile paths #19
• Short-term patch: Handle compact GitHub issue repo paths #20
• Upstream parser/export request: GitHub: export shared mount-path parser for issues and PRs relayfile-adapters#224