Feature/multi source

[chrisribe]

Enables multi source memories to be referenced on search.
This avoids lumping all memories into the same repo (work, personal, AI bot, learnings index)

[chrisribe]

@copilot please review and insure this is ready for main. I have been using it for 2-3 weeks now and did not see issues, but only set and forgot about it so.

[Copilot]

Pull request overview

This PR adds multi-source (federated) memory search to git-mem, enabling users/agents to search a primary memory store plus additional read-only “source” repos without merging them into one repo.

Changes:

• Add git-mem source subcommands (add/list/enable/disable/remove/sync) and update search to query enabled sources with source attribution (including search --json).
• Add a dedicated multi-source test suite and update existing tests for revised commit-count expectations.
• Expand documentation to describe multi-source usage and configuration.

Reviewed changes

Copilot reviewed 9 out of 13 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
git-mem	Implements federated search across sources and adds source management commands.
tests/test-source.sh	New end-to-end suite covering source lifecycle + multi-source search attribution.
tests/test-basic.sh	Updates commit-count expectations to include init/meta commit.
tests/test-sync.sh	Updates sync commit-count expectations to include init/meta commit.
README.md	Documents multi-source feature and updates command/config sections.
MULTI-SOURCE.md	Adds standalone multi-source documentation and design explanation.
SKILL.md	Updates skill docs to mention sources and new env var.
docs/roadmap.md	Marks multi-source work as done and updates test suite counts.
docs/UBIQUITOUS_LANGUAGE.md	Formatting-only adjustments (content unchanged).
docs/benchmark.md	Formatting-only adjustments (content unchanged).
.gitattributes	Enforces LF endings for shell scripts and git-mem for cross-platform safety.
.gitignore	Formatting-only adjustment.
LICENSE	Formatting-only adjustment.

Comments suppressed due to low confidence (2)

git-mem:865

• count_memories only recognizes repos with a .git directory. This disagrees with iter_sources (which accepts a .git file too), and will report 0 entries for valid worktree-style repos.

    [[ ! -d "$path/.git" ]] && echo "0" && return

README.md:38

• The on-disk layout diagram currently claims memory-store/ contains only .git/ and "(no other files)", but git-mem init writes and commits a README.md into the store. Update the diagram so it matches actual behavior.

memory-store/
└── .git/    ← the ENTIRE memory store lives here
             (no other files)

---

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

[Copilot]

@copilot please review and insure this is ready for main. I have been using it for 2-3 weeks now and did not see issues, but only set and forgot about it so.

Addressed the two reviewer findings and the code looks good to merge:

• search_repo (line 227) and count_memories (line 865): changed [[ ! -d "$path/.git" ]] to [[ ! -d "$path/.git" && ! -f "$path/.git" ]] so git worktrees/submodules (which use a .git file) are no longer silently skipped during search.
• source add (line 923): changed [[ -d "$real_path/.git" ]] to [[ -d "$real_path/.git" || -f "$real_path/.git" ]] so worktree-backed repos are correctly detected as local paths instead of falling through to URL detection.

All 7 test suites pass. Commit: fix: accept .git as file (worktree/submodule) in search_repo, count_memories, and source add.