Render semantic Git history as a journey at /journey/ #32

Outcome

Create a better-than-git-sim repository journey that groups raw Git activity into meaningful delivery epochs and lets a reader traverse from intent to shipped evidence.

Scope

• Group commits into explainable chapters using releases, merge boundaries, roadmap steps, ADRs, issues, PRs, and time gaps.
• Render branch/merge lanes, releases, deployments, decision points, quest arcs, and periods of concentrated work.
• Expand from epoch → roadmap/ADR context → issues/PRs → commits/checks → changed files.
• Provide author, path, time, branch, release, roadmap, decision, and status filters.
• Add compare and replay controls with reduced-motion-safe behavior.
• Keep automated grouping rules deterministic and expose why an epoch was formed.
• Make orphan commits and unlinked work visible without shaming or inventing intent.

Acceptance criteria

• The journey is more comprehensible than a chronological commit list for a large repository.
• Grouping rules are deterministic, testable, and explainable.
• Merge topology and release boundaries remain accurate.
• Users can reach canonical commits, diffs, PRs, checks, ADRs, and roadmap steps.
• Orphan/unclassified history is explicitly represented.
• Large histories use pagination/virtualization and remain responsive.
• Replay is optional and fully respects reduced-motion preferences.

Program dependencies

• Parent: Build the Repository Intelligence experience #27
• Contracts: Define the Repository Intelligence event and provenance contract hygiene#19
• Read model: Build the normalized Repository Intelligence graph and query snapshots observatory#7
• Components: Create reusable Repository Intelligence visualization components holon#22