Agent regression: ignores skill hard-gates and executes unapproved actions

## Feedback from user session

**Summary:** The Copilot CLI agent is regressing in two related ways:

1. **Ignores skill hard-gates.** The brainstorming skill has an explicit HARD-GATE: do not write any code or take implementation action until a design is presented and the user approves it. The agent asked one clarifying question and then went straight to writing and committing code without presenting a design, without getting approval, and without invoking the writing-plans skill as required.

2. **Executes unapproved actions autonomously.** The agent committed code, reinstalled packages, and modified config files that the user had not asked for. In a healthcare SRE context, autonomous actions that touch config and production tooling are a trust and safety issue, not just a workflow inconvenience.

3. **Pattern appears to be worsening.** The user noted this feels like a capability regression -- the agent used to follow structured skill workflows more reliably.

**Expected behavior:**
- Skill hard-gates are honored unconditionally
- No code is written, committed, or installed without explicit user approval of a design
- Implementation only begins after brainstorm -> spec -> plan -> user approval

**Impact:** Broken workflow, wasted rework, eroded trust.

Start by reproducing the reported Copilot CLI session and trace how skill hard-gates, approval state, and autonomous actions are handled. The issue names no files or tests; done means the brainstorm → spec → plan → approval sequence is enforced and code, commits, installations, and config changes do not occur without approval.

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