Clean up provenance framing and redundant attribution

[pentaxis93]

Context

PR #4 removed "curated" from methodology-facing docs. The provenance problem runs deeper than terminology — the framing itself is culturally misaligned with OSS norms.

Problems

1. Provenance terms in methodology guidance

"Original" and "curated" appear throughout methodology docs as skill tags and section headers. Agents consuming these docs don't need to know who authored a skill to use it correctly — provenance information in methodology context is noise.

PR #4 addressed some instances. Others remain.

2. Attribution file is redundant

The project doesn't distribute upstream code — it's fetched at install time. When upstream code isn't distributed, there's no attribution obligation to fulfill. A file that exists to satisfy a non-existent requirement adds confusion about what the project's actual licensing posture is.

3. Performative framing signals cultural unfamiliarity

Statements that announce licensing compliance ("Groundwork respects original authorship and licensing") rather than simply complying are a known anti-pattern in OSS culture. Silence backed by correct LICENSE files is the norm. Performative declarations signal unfamiliarity with the culture.

Acceptance criteria

• Methodology docs describe skills by function, not provenance
• No redundant attribution — if upstream code isn't distributed, no attribution obligation exists
• No performative statements about licensing compliance
• cargo test -p groundwork-cli passes

[pentaxis93]

Resolved — ATTRIBUTION.md removed, provenance terminology cleared from methodology docs and CLI. ARCHITECTURE.md uses 'curated' as architecture-level composition terminology, not provenance framing.