refactor(tools): bin/{subject}/{method} layout; Go serve+watch modules

Move serve/ (module) -> bin/server, tools/ -> bin/tools, replace bin/kb-watch
bash with bin/watch Go package; self-executing Go shebangs bin/serve.go and
bin/kb/watch.go; Docker + CI + git/import + docs repointed. Multi-stage image
builds static serve+watch binaries (no Go runtime in container).

bin/tools/gitimport.py

@@ -0,0 +1,117 @@
+"""gitimport - parse `git log` output and turn commits into brain leafs.
+
+Pure, testable functions. Field grammar (see bin/git/import):
+
+  git log --no-merges --name-only \
+      --format='%x1e%H%x1f%an%x1f%ae%x1f%aI%x1f%s'
+
+  0x1e = record separator, 0x1f = field separator.
+  Files: newline-separated lines following each record's subject.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+
+REC_SEP = "\x1e"
+FIELD_SEP = "\x1f"
+
+
+@dataclass
+class Commit:
+    sha: str
+    author: str
+    email: str
+    date: str
+    subject: str
+    files: list[str] = field(default_factory=list)
+
+    def leaf_text(self, repo: str) -> str:
+        head = f"commit {self.sha[:12]} in {repo} — {self.subject}"
+        body = [head, f"Author: {self.author} <{self.email}>", f"Date: {self.date}"]
+        if self.files:
+            body.append("Changing: " + ", ".join(self.files))
+        return "\n".join(body)
+
+
+def parse_log(text: str) -> list[Commit]:
+    """Parse `git log` output into Commit records.
+
+    Records are separated by 0x1e. A record is fields joined by 0x1f,
+    followed by optional newline-separated file paths inside the next
+    segment (git emits blank line + files after each record).
+    """
+    commits: list[Commit] = []
+    # field records and file lists alternate; simpler: split on REC_SEP,
+    # each chunk = header line, possibly followed by newline + files.
+    for chunk in text.split(REC_SEP):
+        chunk = chunk.strip("\n")
+        if not chunk:
+            continue
+        lines = chunk.split("\n", 1)
+        header = lines[0].split(FIELD_SEP)
+        if len(header) < 5:
+            continue
+        sha, author, email, date, subject = header[:5]
+        files = [ln.strip() for ln in lines[1].splitlines() if ln.strip()] if len(lines) > 1 else []
+        commits.append(Commit(sha=sha, author=author, email=email,
+                              date=date, subject=subject, files=files))
+    return commits
+
+
+def commits_to_leafs(commits: list[Commit], repo: str) -> list[dict]:
+    """Map commits to the leaf shape bin/kb/index expects (source/repo/...)."""
+    out: list[dict] = []
+    for c in commits:
+        out.append({
+            "source": f"{repo}@{c.sha}",
+            "repo": repo,
+            "heading": f"commit {c.sha[:12]} — {c.subject}",
+            "text": c.leaf_text(repo),
+            "type": "commit",
+            "status": "current",
+            "related": ",".join(c.files),
+        })
+    return out
+
+
+GIT_SCHEMA = (
+    "CREATE NODE TABLE IF NOT EXISTS Commit (id STRING, repo STRING, subject STRING, "
+    "author STRING, email STRING, date STRING, PRIMARY KEY(id))",
+    "CREATE NODE TABLE IF NOT EXISTS Person (id STRING, name STRING, email STRING, PRIMARY KEY(id))",
+    "CREATE REL TABLE IF NOT EXISTS HAS_VERSION (FROM File TO Commit)",
+    "CREATE REL TABLE IF NOT EXISTS AUTHORED (FROM Commit TO Person)",
+)
+
+
+def ensure_git_schema(conn) -> None:
+    for stmt in GIT_SCHEMA:
+        conn.execute(stmt)
+
+
+def index_commits(conn, commits: list[Commit], repo: str) -> int:
+    """Write Commit/File/Person nodes + edges, one per commit (idempotent by sha)."""
+    ensure_git_schema(conn)
+    for c in commits:
+        conn.execute(
+            "MERGE (c:Commit {id:$sha}) SET c.repo=$repo, c.subject=$subject, "
+            "c.author=$author, c.email=$email, c.date=$date",
+            parameters={"sha": c.sha, "repo": repo, "subject": c.subject,
+                        "author": c.author, "email": c.email, "date": c.date},
+        )
+        conn.execute(
+            "MERGE (p:Person {id:$email}) SET p.name=$name, p.email=$email",
+            parameters={"email": c.email, "name": c.author},
+        )
+        conn.execute("MATCH (c:Commit {id:$sha}), (p:Person {id:$email}) "
+                     "MERGE (c)-[:AUTHORED]->(p)",
+                     parameters={"sha": c.sha, "email": c.email})
+        for path in c.files:
+            conn.execute(
+                "MERGE (f:File {id:$fid}) SET f.path=$path, f.repo=$repo",
+                parameters={"fid": f"{repo}:{path}", "path": path, "repo": repo},
+            )
+            conn.execute("MATCH (f:File {id:$fid}), (c:Commit {id:$sha}) "
+                         "MERGE (f)-[:HAS_VERSION]->(c)",
+                         parameters={"fid": f"{repo}:{path}", "sha": c.sha})
+    return len(commits)