ci: repin rust-toolchain to a master commit, not a moved stable tip

29eef336 was the tip of dtolnay's stable branch when pinned. That branch
force-moves each Rust release, orphaning the commit — reachable from no
ref, so act resolves 'reference not found' and rust-test dies before
compiling. That skipped aarch64-artifact and stopped edge publishing
with nothing saying why. master is append-only.

.gitea/workflows/ci.yml

@@ -25,7 +25,17 @@ jobs:
           git -c http.extraheader="Authorization: token ${{ secrets.LOCAL_GITEA_TOKEN }}" \
             clone "${GITHUB_SERVER_URL}/Fimeg/tuie.git" /workspace/Fimeg/tuie
           git -C /workspace/Fimeg/tuie checkout aa43e335c8f5a3cd2c78e397a1a8dfe534a6bc35
-      - uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8
+      # Pinned to a MASTER commit, deliberately, not to a `stable`-branch tip.
+      # The old pin (29eef336, "toolchain: stable") was the tip of that repo's
+      # `stable` branch when it was taken. dtolnay force-moves `stable` on every
+      # Rust release, which orphaned the commit: it still exists as an object on
+      # GitHub, but is reachable from no ref, so act's clone resolves it as
+      # "reference not found" and rust-test dies before it compiles anything.
+      # That failure skipped aarch64-artifact and silently stopped publishing to
+      # `edge` — the phone sat on an old build with nothing saying why.
+      # master is append-only, so a commit on it stays reachable. The toolchain
+      # is chosen by the `toolchain:` input below, never by the branch.
+      - uses: dtolnay/rust-toolchain@2c7215f132e9ebf062739d9130488b56d53c060c
         with:
           toolchain: "1.94"
           components: clippy