docs: document merge strategies and fast-forward merge method

[jd]

Add a new Merge Strategies guide page covering all four merge methods
(merge, squash, rebase, fast-forward) with git history diagrams, a
comparison table, and a decision matrix.

Update queue rules reference to document merge_method: fast-forward
and its requirements (batch_size: 1, max_parallel_checks: 1, branch
protection bypass).

Clarify the batches page to distinguish queue_branch_merge_method
(batch branch merging) from merge_method (individual PR merging).

Closes Mergifyio/mergify#67

Co-Authored-By: Claude Opus 4.6 (1M context) noreply@anthropic.com

[mergify]

Merge Protections

Your pull request matches the following merge protections and will not be merged until they are valid.

🔴 👀 Review Requirements

This rule is failing.

• any of:
  • #approved-reviews-by >= 2
  • author = dependabot[bot]
  • author = mergify-ci-bot

🔴 🔎 Reviews

This rule is failing.

• #review-requested = 0
• #review-threads-unresolved = 0
• #changes-requested-reviews-by = 0

🟠 🤖 Continuous Integration

Waiting checks: test-broken-links.

• all of:
  • any of:
    • check-success = test-broken-links
    • label = ignore-broken-links
  • check-success = build
  • check-success = lint
  • check-success = test
  • any of:
    • check-success=Cloudflare Pages
    • -head-repo-full-name~=^Mergifyio/

🟢 Enforce conventional commit

Wonderful, this rule succeeded.

Make sure that we follow https://www.conventionalcommits.org/en/v1.0.0/

• title ~= ^(fix|feat|docs|style|refactor|perf|test|build|ci|chore|revert)(?:\(.+\))?:

🟢 📕 PR description

Wonderful, this rule succeeded.

• body ~= (?ms:.{48,})

[Copilot]

Pull request overview

Adds a new documentation guide for merge strategies in the Merge Queue section and updates existing Merge Queue docs to reference/clarify the new merge_method: fast-forward behavior and the distinction between PR merge method vs batch-branch merge method.

Changes:

• Add a new “Merge Strategies” guide page with diagrams and comparison/decision tables.
• Document merge_method: fast-forward in queue rules docs and link to the new guide.
• Clarify on the batches page the difference between queue_branch_merge_method (batch branch) and merge_method (individual PRs).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
src/content/navItems.tsx	Adds “Merge Strategies” to the Merge Queue navigation.
src/content/docs/merge-queue/rules.mdx	Documents merge_method including fast-forward and links to the new guide.
src/content/docs/merge-queue/merge-strategies.mdx	New guide page explaining merge methods, tradeoffs, diagrams, and fast-forward requirements.
src/content/docs/merge-queue/batches.mdx	Clarifies queue_branch_merge_method vs merge_method and refines the fast-forward note.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.