chore(weights): update vanguarstew and genie-claw weight settings

[vanguarstew]

Weight Adjustment PR

Changes Summary

Metric	Total
Repositories Added	0
Repositories Removed	0
Weights Modified	2
Net Weight Change	0

Justification

Raise Geniepod/genie-claw's maintainer_cut from 0.3 to 0.5 to increase maintainer support for another repository operated by the same maintainer.

For gittensor-vanguard/vanguarstew, leave maintainer_cut at its original 0.5, retain fixed_base_score: 1.0, set default_label_multiplier from 0.0 to 0.02, and remove the mult:contribution label multiplier. This establishes the small default multiplier directly while retiring the flat contribution label; the measured perf:* tiers remain available for higher-value contributions.

Emission shares are unchanged, so the registry's total emission allocation is unaffected.

Validation

• Parsed the registry as JSON.
• Checked live registry numeric ranges and total emission invariants.
• Asserted the requested values and removal exactly.
• Confirmed the diff contains only gittensor/validator/weights/master_repositories.json.
• Ran git diff --check.

Additional Acceptable Branches

• No additional_acceptable_branches changes in this PR

Checklist

• Changes summary table is filled in accurately
• Net weight changes are justified in the Justification section
• Added repositories have correct branch and initial weight