feat(desktop): open repository files from message links

[yinkev]

Summary

• add a strict first-party buzz://repo URI contract for hosted repository files and directories
• preserve repository links through Markdown sanitization and route clicks inside Buzz rather than through the OS
• navigate to the canonical project, force the hosted repository source, select the requested branch or commit, and open the requested file or directory
• let the native repository snapshot include a bounded focused path beyond the normal 250-entry tree cap
• fail closed on malformed coordinates and offer Open repository root when a ref or path is unavailable

Closes #2906.

Duplicate search: no overlapping open pull request found; this implements the existing issue above.

URI contract

buzz://repo?owner=<64-hex-pubkey>&repo=<repo-id>&ref=<branch-or-commit>&path=<repository-relative-path>

The parser rejects credentials, ports, extra URI path components, fragments, unknown or duplicate parameters, malformed identifiers, absolute paths, backslashes, control characters, empty components, and . / .. traversal.

Arbitrary file:// access is deliberately unchanged.

Implementation

• Markdown runtime: preserves and renders valid buzz://repo anchors, including context-menu copy/open behavior
• Navigation: maps stable repository identity plus repoRef / repoPath search state into the project route
• Project route: validates repository target search atomically so incomplete or unsafe state is discarded
• Repository viewer: synchronously uses the hosted snapshot for repository links, opens the Files tab, resolves files/directories after the requested snapshot loads, retries after ref recovery or snapshot replacement, and exposes repository-root recovery
• Native snapshot: uses NUL-delimited git ls-tree output, safely matches non-ASCII paths, and appends only the exact file or bounded directory descendants outside the normal tree cap
• Explicit refs: validated refs/heads/, refs/tags/, and refs/nostr/ targets stay on the explicit fetch path; unavailable branches fail instead of silently cloning the default branch
• Repository identity: explicit links always fetch from the canonical project clone URL rather than an active pull request's alternate/fork URL

This PR implements the Desktop vertical slice while keeping the URI stable for independent web/mobile adoption.

Testing

• parser/build/round-trip and adversarial URI tests
• Markdown URL-transform regression tests for buzz://repo, buzz://message, external links, and unsafe schemes
• route-search validation, ref-precedence, canonical-clone, and synchronous-source tests
• repository-target file/directory/missing/retry/root-recovery tests
• native focus-path validation, cap, exact-file, directory-prefix, non-ASCII, and explicit branch-ref tests
• focused Tauri tests — 13 passed
• Tauri cargo fmt --check
• Tauri Clippy with warnings denied
• changed-file Biome checks
• pnpm typecheck
• full Desktop suite — 3,540 passed
• Desktop production build — passed

Current gate dependency

Current main independently exceeds the existing managed_agents/runtime.rs file-size ratchet after #2176. #2930 restores that gate without changing runtime behavior and has a fully successful GitHub CI run. This PR remains draft until that prerequisite lands and this branch is rebased; no unrelated ratchet workaround is included here.

[yinkev]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 2f0f7fa7ba

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[yinkev]

@codex address that feedback

[chatgpt-codex-connector]

To use Codex here, create an environment for this repo.

[yinkev]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: ddd668288d

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[yinkev]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: b261069307

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".