feat(agents): wire xAI provider, move @lead to xai/grok-4.5 (issue #12)

Add an xai provider (OpenAI-compatible, https://api.x.ai/v1) to
install-opencode.sh, with its models map derived from agents.json
exactly like the ollama providers. Pass XAI_API_KEY into both the
Install-opencode and Run-agent steps of agent.yml. Switch @lead's
model from anthropic/claude-opus-4-8 to xai/grok-4.5 (vision-capable,
so @lead keeps image reading). All other agents unchanged;
ANTHROPIC_API_KEY is retained for @ops and not removed.

.gitea/workflows/agent.yml

@@ -149,6 +149,7 @@ jobs:
           SCRIPTS: ${{ runner.temp }}/agents-scripts
           OLLAMA_URL: ${{ secrets.OLLAMA_URL }}
           OLLAMA_CLOUD_API_KEY: ${{ secrets.OLLAMA_CLOUD_API_KEY }}
+          XAI_API_KEY: ${{ secrets.XAI_API_KEY }}
           NAME: ${{ steps.prep.outputs.name }}
           SKILLS: ${{ steps.prep.outputs.skills }}   # JSON array of skills this agent may load
         run: bash "$SCRIPTS/install-opencode.sh"
@@ -212,6 +213,7 @@ jobs:
         env:
           SCRIPTS: ${{ runner.temp }}/agents-scripts
           ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
+          XAI_API_KEY: ${{ secrets.XAI_API_KEY }}
           # SELF_TOKEN = the RUNNING agent's OWN token (TOKEN_PM for @pm, TOKEN_OPS for @ops, …).
           # Only this agent's token is placed in its process env, so no agent can act as another.
           # Powers the gitea-api / gitea-admin skills — each agent calls Gitea as itself. Every

.gitea/workflows/scripts/agents.json

@@ -25,7 +25,7 @@
     "desc": "Senior dev — complex, multi-file implementation (GLM-5.2 via Ollama Cloud, text-only)."
   },
   "lead": {
-    "model": "anthropic/claude-opus-4-8",
+    "model": "xai/grok-4.5",
     "vision": true,
     "mode": "pr",
     "skills": [

.gitea/workflows/scripts/install-opencode.sh

@@ -1,8 +1,8 @@
 #!/usr/bin/env bash
 # Install opencode + provider config (+ Playwright MCP for browser agents).
 #
-# Required env (provided by the workflow step): OLLAMA_URL OLLAMA_CLOUD_API_KEY NAME SKILLS
-#   GITHUB_PATH HOME
+# Required env (provided by the workflow step): OLLAMA_URL OLLAMA_CLOUD_API_KEY XAI_API_KEY
+#   NAME SKILLS GITHUB_PATH HOME
 set -eu
 
 # PIN the opencode version: an unpinned `latest` means a breaking release (CLI flags, or the
@@ -42,15 +42,18 @@ PERM=$(jq -nc --argjson s "$SKILLS" '
 # The provider `models:` maps are DERIVED from agents.json (the single source of truth, shared with
 # route.sh) so every model an agent is routed to is always declared in the provider config.
 # `ollama-cloud/` prefix models go to the cloud provider; `ollama/` prefix models go to the local
-# provider. Built-in providers (e.g. `anthropic/claude-opus-4-8` for @lead) are not derived here.
+# provider. `xai/` prefix models go to the xAI provider (OpenAI-compatible, https://api.x.ai/v1).
+# Built-in providers (e.g. `anthropic/claude-opus-4-8` for @ops) are not derived here.
 # See issue #31.
 AGENTS_JSON="${SCRIPTS:-$(dirname -- "$0")}/agents.json"
 CLOUD_MODELS=$(jq -r '[.[] | .model | select(startswith("ollama-cloud/")) | sub("^ollama-cloud/";"")] | map({(.):{}}) | add // {}' "$AGENTS_JSON")
 LOCAL_MODELS=$(jq -r '[.[] | .model | select(startswith("ollama/")) | sub("^ollama/";"")] | map({(.):{}}) | add // {"ornith:35b":{}}' "$AGENTS_JSON")
-jq -n --argjson mcp "$MCP" --argjson perm "$PERM" --argjson cloud "$CLOUD_MODELS" --argjson local "$LOCAL_MODELS" --arg url "$OLLAMA_URL" --arg ckey "$OLLAMA_CLOUD_API_KEY" '{
+XAI_MODELS=$(jq -r '[.[] | .model | select(startswith("xai/")) | sub("^xai/";"")] | map({(.):{}}) | add // {}' "$AGENTS_JSON")
+jq -n --argjson mcp "$MCP" --argjson perm "$PERM" --argjson cloud "$CLOUD_MODELS" --argjson local "$LOCAL_MODELS" --argjson xai "$XAI_MODELS" --arg url "$OLLAMA_URL" --arg ckey "$OLLAMA_CLOUD_API_KEY" --arg xkey "$XAI_API_KEY" '{
   provider: {
     ollama: {npm:"@ai-sdk/openai-compatible", options:{baseURL:($url+"/v1")}, models:$local},
-    "ollama-cloud": {npm:"@ai-sdk/openai-compatible", options:{baseURL:"https://ollama.com/v1", apiKey:$ckey}, models:$cloud}
+    "ollama-cloud": {npm:"@ai-sdk/openai-compatible", options:{baseURL:"https://ollama.com/v1", apiKey:$ckey}, models:$cloud},
+    xai: {npm:"@ai-sdk/openai-compatible", options:{baseURL:"https://api.x.ai/v1", apiKey:$xkey}, models:$xai}
   },
   permission: $perm,
   mcp: $mcp