fix(gbrain): canonicalize remotes with trailing slashes

lib/gstack-memory-helpers.ts

@@ -106,9 +106,15 @@ export function canonicalizeRemote(url: string | null | undefined): string {
     // strip user@ prefix on URL-style remotes
     s = s.replace(/^[^@\/]+@/, "");
   }
+  // strip trailing slash(es) first, so a URL written with a trailing slash
+  // still matches the `.git$` suffix below (e.g. ".../repo.git/" must
+  // canonicalize to ".../repo", not ".../repo.git").
+  s = s.replace(/\/+$/, "");
   // strip trailing .git
   s = s.replace(/\.git$/i, "");
-  // strip trailing slash
+  // re-strip trailing slash(es): a path remote ending in a `.git` directory
+  // component ("/repo/.git") exposes a new trailing slash once `.git` is
+  // stripped, which would split the repo into a second identity.
   s = s.replace(/\/+$/, "");
   // collapse multiple slashes (after path normalization)
   s = s.replace(/\/{2,}/g, "/");

test/gstack-memory-helpers.test.ts

@@ -67,6 +67,30 @@ describe("canonicalizeRemote", () => {
   it("collapses redundant slashes", () => {
     expect(canonicalizeRemote("https://github.com//foo//bar")).toBe("github.com/foo/bar");
   });
+
+  it("strips .git even when the URL has a trailing slash", () => {
+    // A remote configured with both a .git suffix and a trailing slash must
+    // canonicalize to the same key as one without — otherwise the same repo
+    // gets two dedup/source-id keys across machines.
+    expect(canonicalizeRemote("https://github.com/garrytan/gstack.git/")).toBe("github.com/garrytan/gstack");
+    expect(canonicalizeRemote("git@github.com:garrytan/gstack.git/")).toBe("github.com/garrytan/gstack");
+    expect(canonicalizeRemote("https://github.com/foo/bar.git///")).toBe("github.com/foo/bar");
+  });
+
+  it("produces the same key with or without a trailing slash", () => {
+    expect(canonicalizeRemote("https://github.com/garrytan/gstack.git/")).toBe(
+      canonicalizeRemote("https://github.com/garrytan/gstack.git")
+    );
+  });
+
+  it("canonicalizes a path remote ending in a .git directory component", () => {
+    // Stripping the `.git` suffix exposes a new trailing slash
+    // ("/repo/.git" → "/repo/") which must also be stripped, or the same
+    // repo splits into two identities.
+    expect(canonicalizeRemote("file:///Users/x/repo/.git")).toBe(
+      canonicalizeRemote("file:///Users/x/repo")
+    );
+  });
 });
 
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