Feat/emission share allocation

[tao-hunter]

Summary

• Replaces registry weight (used as a per-PR multiplier) with emission_share: each repo’s share of the unified 90% scoring pool (OSS_EMISSION_SHARE), enforced at round allocation in allocate_round_emissions, not in the per-PR multiplier chain.
• Adds issue_discovery_share on RepositoryConfig (default 0.5): splits each repo’s slice between PR scoring and issue discovery, with same-repo spill when one side has no eligible weight; recycle only when both sides are empty.
• Removes repo_weight from earned-score math (legacy + mirror PRs + issue discovery); repo_weight_multiplier / discovery_repo_weight_multiplier stay 1.0 for DB/schema compatibility where needed.
• Monetary policy: Drops the fixed 45% recycle floor. RECYCLE_UID only receives registry slack (1 − Σ emission_share) × OSS_EMISSION_SHARE and unclaimed per-repo slices (no redistribution to other repos). Treasury is a flat 10% to UID 111 (ISSUES_TREASURY_EMISSION_SHARE trimmed from 15%).
• Migrates master_repositories.json: weight → emission_share, preserving relative weights and normalizing so Σ emission_share = 1.0. Loader validates [0, 1] per entry and Σ ≤ 1 (strict > 1 → empty registry).
• Pipeline: get_rewards returns evaluations only (no global OSS normalize); allocate_round_emissions runs after issue discovery. CLI gitt miner score uses the same path; rewards JSON highlights blended_final.
• Test fixes: remaining RepositoryConfig(weight=...) in test_label_multiplier.py and test_load.py updated to emission_share for pyright/pytest.

Related Issues

• Closes Convert per-repo weight from unbounded multiplier to emission_share (bounded pool slice) #1215

Type of Change

• Bug fix
• New feature
• Refactor
• Documentation
• Other (emission / monetary policy — recycle no longer a fixed baseline)

Testing

• tests/validator/test_emission_allocation.py — allocation, slack, spill, slice vs PR count.
• tests/validator/test_load_weights.py — emission_share invariants + JSON fixtures.
• Mirror/legacy scoring, label, review-quality, CLI miner-score, test_load / test_label_multiplier updated for RepositoryConfig(emission_share=...).
• Full pytest + pyright in CI / local (dev env: uv pip install -e ".[dev]" for pre-commit hooks).
• Manual: one validator round — rewards.sum() ≈ 1.0 when treasury + recycle UIDs exist on metagraph.

Checklist

• Code style / ruff / pre-commit (after dev install).
• Self-review; focused diff (no accidental lockfile churn unless intentional).
• Maintainer-facing docs / changelog if required for emission policy.
• PR text calls out recycle baseline removal and 90/10 split explicitly.