ci(.github/workflows): self-install Python 3.11 via uv on the peco-driver runner

actions/setup-python can't provision Python on the self-hosted peco-driver
runner (no GitHub hosted tool-cache; it can't reach the version manifest —
"version 3.11 not found for this operating system"). Replace it in all four
bot workflows with a self-contained step that fetches Python itself:

  - bootstrap uv from PyPI via the system python3 (the runner already reaches
    PyPI — it pip-installs claude-agent-sdk),
  - `uv venv --python 3.11 --seed` pulls a standalone CPython 3.11 from GitHub
    (already reachable — the engine installs from github.com) into a seeded
    venv (with pip), put on PATH so later `pip`/`python -m` steps are unchanged.

No runner provisioning or root needed.

Co-authored-by: Isaac

Author: eric-wang-1990

.github/workflows/engineer-bot-followup.yml

@@ -178,9 +178,18 @@ jobs:
 
       - name: Setup Python
         if: steps.filter.outputs.skip != 'true'
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
-        with:
-          python-version: '3.11'
+        shell: bash
+        # actions/setup-python can't provision on this self-hosted runner
+        # (no hosted tool-cache, can't reach the version manifest). Install
+        # Python ourselves: bootstrap uv from PyPI via system python3 (the
+        # runner already reaches PyPI for claude-agent-sdk), then let uv fetch
+        # a standalone CPython 3.11 from GitHub and build a SEEDED venv (with
+        # pip) so later `pip install` / `python -m` steps work unchanged.
+        run: |
+          python3 -m pip install --quiet --user uv
+          export PATH="$(python3 -m site --user-base)/bin:$PATH"
+          uv venv --python 3.11 --seed "$RUNNER_TEMP/bot-venv"
+          echo "$RUNNER_TEMP/bot-venv/bin" >> "$GITHUB_PATH"
 
       - name: Setup .NET
         if: steps.filter.outputs.skip != 'true'

.github/workflows/engineer-bot.yaml

@@ -109,9 +109,18 @@ jobs:
           git config user.email "${bot_id}+${bot_login}@users.noreply.github.com"
 
       - name: Setup Python
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
-        with:
-          python-version: '3.11'
+        shell: bash
+        # actions/setup-python can't provision on this self-hosted runner
+        # (no hosted tool-cache, can't reach the version manifest). Install
+        # Python ourselves: bootstrap uv from PyPI via system python3 (the
+        # runner already reaches PyPI for claude-agent-sdk), then let uv fetch
+        # a standalone CPython 3.11 from GitHub and build a SEEDED venv (with
+        # pip) so later `pip install` / `python -m` steps work unchanged.
+        run: |
+          python3 -m pip install --quiet --user uv
+          export PATH="$(python3 -m site --user-base)/bin:$PATH"
+          uv venv --python 3.11 --seed "$RUNNER_TEMP/bot-venv"
+          echo "$RUNNER_TEMP/bot-venv/bin" >> "$GITHUB_PATH"
 
       - name: Setup .NET
         uses: actions/setup-dotnet@67a3573c9a986a3f9c594539f4ab511d57bb3ce9  # v4.3.1

.github/workflows/reviewer-bot-followup.yml

@@ -157,9 +157,18 @@ jobs:
 
       - name: Setup Python
         if: steps.filter.outputs.skip != 'true'
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
-        with:
-          python-version: '3.11'
+        shell: bash
+        # actions/setup-python can't provision on this self-hosted runner
+        # (no hosted tool-cache, can't reach the version manifest). Install
+        # Python ourselves: bootstrap uv from PyPI via system python3 (the
+        # runner already reaches PyPI for claude-agent-sdk), then let uv fetch
+        # a standalone CPython 3.11 from GitHub and build a SEEDED venv (with
+        # pip) so later `pip install` / `python -m` steps work unchanged.
+        run: |
+          python3 -m pip install --quiet --user uv
+          export PATH="$(python3 -m site --user-base)/bin:$PATH"
+          uv venv --python 3.11 --seed "$RUNNER_TEMP/bot-venv"
+          echo "$RUNNER_TEMP/bot-venv/bin" >> "$GITHUB_PATH"
 
       - name: Install bot engine (interim PAT git-install) + Claude SDK/CLI
         if: steps.filter.outputs.skip != 'true'

.github/workflows/reviewer-bot.yml

@@ -89,9 +89,18 @@ jobs:
           persist-credentials: false
 
       - name: Setup Python
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
-        with:
-          python-version: '3.11'
+        shell: bash
+        # actions/setup-python can't provision on this self-hosted runner
+        # (no hosted tool-cache, can't reach the version manifest). Install
+        # Python ourselves: bootstrap uv from PyPI via system python3 (the
+        # runner already reaches PyPI for claude-agent-sdk), then let uv fetch
+        # a standalone CPython 3.11 from GitHub and build a SEEDED venv (with
+        # pip) so later `pip install` / `python -m` steps work unchanged.
+        run: |
+          python3 -m pip install --quiet --user uv
+          export PATH="$(python3 -m site --user-base)/bin:$PATH"
+          uv venv --python 3.11 --seed "$RUNNER_TEMP/bot-venv"
+          echo "$RUNNER_TEMP/bot-venv/bin" >> "$GITHUB_PATH"
 
       - name: Install bot engine (interim PAT git-install) + Claude SDK/CLI
         env: