Trim user-config template: drop voice duplication + several process rules

[virtualian]

Context

~/.claude/marr/MARR-USER-CLAUDE.md was rationalised against the persona file (~/.claude/CLAUDE-USER.md), which solely owns response voice/tone. The local user-config was edited to remove the imperatives listed below. Raising this so the change is folded into the marr CLI's user-config template and not regenerated back on the next marr run.

The three-file import structure is unchanged: ~/.claude/CLAUDE.md continues to import both CLAUDE-USER.md (persona) and marr/MARR-USER-CLAUDE.md (engineering/process).

Removed (15 imperatives)

• Communication Style — entire section (concise-unless-asked, answer-directly, don't-flatter, stand-your-ground, never-assume-user-correct). Duplicated the persona file's voice rules; persona now solely owns voice.
• Work Habits: "prefer editing existing files over creating new ones"; "only create files when absolutely necessary".
• Simplicity: "three similar lines beat a premature helper function"; "only add complexity when clearly necessary".
• Prompt File Principles: "never modify prompt files without explicit approval".
• Attribution Restrictions: "never add AI attribution comments"; "no 'Generated with Claude' / 'Co-Authored-By' comments".
• Testing — entire section (run tests before committing; follow existing test patterns; never assume test frameworks).

Kept (17 imperatives)

• Work Habits: check existing patterns first.
• Simplicity: don't over-engineer; avoid premature abstraction.
• Prompt File Principles: WHAT/WHY-not-HOW; no code/commands/config in prompts; implementation details belong in project docs.
• Attribution: code and docs stand on merit, not origin.
• Before Modifying Code: read code first; review patterns; check project config.
• Security: never commit secrets; use env vars; validate inputs at boundaries.
• Documentation Organization: full section retained.

Intentional behavioural implications

• Dropping the Prompt File "no-edit-without-approval" rule removes MARR's approval gate on editing prompt/standard files.
• Dropping the two attribution bans removes MARR's prohibition on AI attribution and Co-Authored-By; only the softer "stand on merit" principle remains.
• Dropping the Testing section removes MARR's run-tests-before-commit discipline.

Requested

Fold these removals into the marr CLI user-config template so a regenerate does not reintroduce them.