Replace Gemini coding agent with Antigravity (#6900)

* Replace Gemini coding agent with Antigravity

* Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Remove the dead Gemini mise wrapper in the Antigravity migration

Remove Preinstalls no longer lists gemini, so the wrapper Omarchy created
would have stayed in ~/.local/bin with nothing left to clean it up.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Install Antigravity when it is the default a Gemini user is migrated onto

The opt-out check skipped the install but the rewrite ran anyway, so anyone
who had removed the preinstalls was left with a default agent naming a
command that is not there.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Fix Antigravity skill provisioning and Gemini wrapper migration

- Wires Omarchy's default skills into Antigravity by linking them to ~/.gemini/config/skills/ in bin/omarchy-provision-user and migrations/1786719479.sh.
- Fixes the Gemini wrapper migration in migrations/1786719479.sh to recognize and remove wrappers containing either `mise use -g "gemini"` or `mise use -g --quiet "gemini"`, while leaving hand-written wrappers intact.
- Adds regression tests for both skill provisioning and wrapper removal in test/shell.d/default-agent-test.sh and test/shell.d/provision-user-test.sh.

* Stop the provisioning test from retheming the session it runs in

The test ran the real omarchy-provision-user, which sources install/user/all.sh and so reached omarchy-theme-set: hyprctl reload against the live compositor, gsettings against the live desktop, and a global Node install, none of which the skill symlinks it asserts need. Its mocks for omarchy-done and omarchy-refresh-applications were shadowed anyway, because provisioning prepends $OMARCHY_PATH/bin ahead of them, so stubbing the install suite at its own path is what a mock cannot do here. The exit status is checked rather than discarded: the assertion held even when provisioning died outright, because the symlinks are made twenty lines before the suite runs.

* Match the Gemini default and wrapper the way Omarchy writes them

The migration decided both questions differently from the code that owns them. It read the default agent with grep -qxF, while omarchy-default-agent takes the first line through read, so a padded "  gemini  " that the launcher still resolves was left naming an agent the launcher no longer supports. The wrapper it deletes was matched anywhere in the file, so a hand-written one that only mentions the installer's line in a comment went with Omarchy's own. Reading it the launcher's way and anchoring the match settles both against whoever wrote the file. The skills loop guards its glob the way migrations/1786539345.sh does, so an empty source cannot leave a symlink named "*" behind a migration already marked complete.

Co-Authored-By: Codex XHigh <noreply@anthropic.com>

* List Antigravity among the skill directories

The manual named Claude Code, Codex, Pi and the generic location; provisioning now links ~/.gemini/config/skills too.

Co-Authored-By: Codex XHigh <noreply@anthropic.com>

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: David Heinemeier Hansson <david@hey.com>
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Omabot <omabot@omarchy.org>

migrations/1786719479.sh

@@ -0,0 +1,41 @@
+echo "Replace the Gemini coding agent with Antigravity"
+
+OMARCHY_PATH="${OMARCHY_PATH:-/usr/share/omarchy}"
+
+agent_file="$HOME/.config/omarchy/defaults/agent"
+skills_source="$OMARCHY_PATH/default/agents/skills"
+
+# Read the default the way omarchy-default-agent reads it, so this migration and
+# the launcher always agree on which agent is selected.
+selected_agent=""
+if [[ -f $agent_file ]]; then
+  read -r selected_agent <"$agent_file" || true
+fi
+
+# Choosing Gemini was opting into an agent, so its replacement follows even for
+# someone who removed the preinstalls. Otherwise the default rewritten below
+# would name a command that is not there.
+if omarchy-cmd-missing agy &&
+  { [[ $selected_agent == "gemini" ]] || [[ ! -f $HOME/.local/state/omarchy/preinstalls-removed ]]; }; then
+  omarchy-mise-install antigravity-cli agy
+fi
+
+if [[ $selected_agent == "gemini" ]]; then
+  printf '%s\n' agy >"$agent_file"
+fi
+
+# Remove Preinstalls no longer lists gemini, so Omarchy's own wrapper would
+# linger with nothing left to clean it up. Anchored to the line the installer
+# writes, so a hand-written wrapper that merely mentions it is left alone.
+if [[ -f $HOME/.local/bin/gemini ]] && grep -Eq '^mise use -g .*"gemini"' "$HOME/.local/bin/gemini"; then
+  rm -f "$HOME/.local/bin/gemini"
+fi
+
+if [[ -d $skills_source ]]; then
+  mkdir -p "$HOME/.gemini/config/skills"
+  for skill in "$skills_source"/*/; do
+    [[ -d $skill ]] || continue
+    name=${skill%/}
+    ln -sfn "$name" "$HOME/.gemini/config/skills/${name##*/}"
+  done
+fi