Add an auto-merge indicator to the PR badge

[0101]

Problem

When a PR has GitHub auto-merge (or Azure DevOps auto-complete) set, it will merge itself as soon as the remaining checks and policies pass. Treemon showed no sign of this, so a worktree with a fully hands-off PR looked identical to one still waiting on a human to press merge.

Changes

• AutoMergeEnabled: bool added to PrInfo in src/Shared/Types.fs
• Parsed from data already present in the existing PR-list responses, so no extra provider calls:
  • GitHub: auto_merge in /pulls (object → true, null/absent → false)
  • AzDo: autoCompleteSetBy in az repos pr list (identity → true, null/absent → false)
• Both providers keep the field populated after the PR merges, so parsing forces false for merged PRs — the flag is only meaningful while the PR is open. MergedPrStore fallbacks are likewise always false, and the fact is not persisted.
• Dashboard renders a mauve check-in-circle glyph on the PR badge (autoMergeIcon in CardViews.fs). The existing .conflict-icon CSS was generalized to a shared .pr-icon class with conflict / auto-merge colour modifiers.
• tm status gains a matching auto-merge flag alongside draft / merged / conflicts.
• Demo fixture exercises the new state; spec section added to docs/spec/worktree-monitor.md.

Tests

dotnet test src/Tests/Tests.fsproj --filter "Category=Fast" — 1710 passed, 0 failed (5m 27s).

New coverage: GitHub and AzDo fixture parsing (set, null, absent, and merged-PR cases), CLI flag rendering, dashboard badge markup, and MergedPrStore fallback.

[Copilot]

Pull request overview

Adds provider-aware auto-merge status to PR data and surfaces it in the dashboard and CLI.

Changes:

• Parses GitHub auto-merge and Azure DevOps auto-complete state.
• Displays an auto-merge icon and CLI status flag.
• Adds provider, persistence, CLI, and dashboard coverage.

Show a summary per file

File	Description
src/Shared/Types.fs	Adds auto-merge state to PrInfo.
src/Server/PrStatus.fs	Parses Azure DevOps auto-complete state.
src/Server/GithubPrStatus.fs	Parses GitHub auto-merge state.
src/Server/MergedPrStore.fs	Defaults restored merged PRs to no auto-merge.
src/Server/DemoFixture.fs	Demonstrates the indicator.
src/Client/CardViews.fs	Renders the auto-merge icon.
src/Client/index.html	Adds shared PR icon styling.
src/Cli/Program.fs	Adds the auto-merge flag.
src/Tests/AzDoFixtureTests.fs	Tests Azure DevOps parsing.
src/Tests/GithubFixtureTests.fs	Tests GitHub parsing.
src/Tests/CliTests.fs	Tests CLI formatting.
src/Tests/DashboardTests.fs	Tests dashboard rendering.
src/Tests/MergedPrStoreTests.fs	Tests fallback behavior.
src/Tests/PrFilteringTests.fs	Updates PR fixtures.
src/Tests/SchedulerTests.fs	Updates scheduler test data.
src/Tests/fixtures/worktrees.json	Adds serialized fixture values.
src/Tests/fixtures/github/pr-list.json	Adds enabled GitHub data.
src/Tests/fixtures/github/pr-list-with-closed.json	Adds null and merged GitHub cases.
src/Tests/fixtures/azdo/pr-list.json	Adds Azure DevOps cases.
docs/spec/worktree-monitor.md	Documents the indicator and persistence behavior.

Review details

• Files reviewed: 20/20 changed files
• Comments generated: 0
• Review effort level: Medium