Add prettier CI gate documentation to 4 workspace AGENTS.md files that omit it

What happened

The boost workspace AGENTS.md repeatedly caused prettier CI failures because the formatting gate was undocumented or insufficiently prominent — first in PR #4189 (leading to #4219), then again in PR #4312 (leading to #4327 and this PR #4330). Each failure required human intervention (/fs-fix) and ~12-14 min of fix agent time.

Investigating whether this gap is systemic, I audited all 7 workspace AGENTS.md files. Only 3 of 7 mention prettier (boost after PR #4330, x2a, and cost-management). The remaining 4 — ai-integrations, intelligent-assistant, mcp-integrations, and scorecard — have zero prettier documentation despite prettier being a repo-level CI gate enforced on all workspaces.

What could go better

The retro agent correctly identifies and fixes this class of issue one workspace at a time, but doesn't check whether sibling workspaces have the same gap. This means the system waits for each workspace to independently fail CI before fixing its AGENTS.md — a reactive pattern that costs ~12 min of fix agent time plus human intervention per failure.

The rhdh-workspace skill does mention yarn prettier:check in its "Before finishing" section, which should theoretically catch this regardless of what workspace AGENTS.md says. However, the evidence from PR #4312 shows that agents prioritize the workspace-specific Build & verify table over the skill's instructions, so the workspace docs need to be complete.

Confidence: High that these 4 workspaces will eventually hit the same CI failure if agents make formatting-sensitive changes there. The prettier check is repo-wide, not boost-specific.

Proposed change

Add prettier documentation to the 4 workspace AGENTS.md files that currently omit it:

1. workspaces/ai-integrations/AGENTS.md — add yarn prettier:fix to the Build & Test Commands section
2. workspaces/intelligent-assistant/AGENTS.md — add a prettier line (this file is only 28 lines; even a brief mention helps)
3. workspaces/mcp-integrations/AGENTS.md — add a prettier line (34 lines; similarly sparse)
4. workspaces/scorecard/AGENTS.md — add yarn prettier:fix to the Build & Test Commands section

The format should match each workspace's existing documentation style (not all use boost's table format). The x2a workspace is a good reference for thorough prettier documentation.

Validation criteria

After the change: grep -rl 'prettier' workspaces/*/AGENTS.md | wc -l should return 7 (all workspaces). The next 5 code/fix agent runs across any of these 4 workspaces should not fail CI due to prettier formatting mismatches.

Generated by retro agent from https://github.com/redhat-developer/rhdh-plugins/pull/4330

Compare the four named files—workspaces/ai-integrations/AGENTS.md, workspaces/intelligent-assistant/AGENTS.md, workspaces/mcp-integrations/AGENTS.md, and workspaces/scorecard/AGENTS.md—with the x2a AGENTS.md reference. Update each using its existing documentation style, then run grep -rl 'prettier' workspaces/*/AGENTS.md | wc -l; done is a result of 7.