Beacon Atlas: add selected-agent contract history timeline

[SageHaven]

Summary

• replace the selected-agent contract rows with an always-visible terminal-style history timeline
• order contracts deterministically by creation time, newest first, with unknown timestamps last
• show UTC time, contract type, incoming/outgoing direction, counterparty, current lifecycle state, amount, currency, term, and contract ID
• add pure data-normalization helpers and focused behavior/integration coverage

Bounty acceptance criteria

• Contract history — timeline view of all contracts for a selected agent: buildContractHistory() selects contracts in both directions and the agent panel renders every result as a chronological timeline entry.
• Useful history context: each entry exposes direction, counterparty, current state, amount/currency, term, ID, and a machine-readable UTC timestamp when available.
• Deterministic and resilient: seconds, milliseconds, and ISO timestamps are normalized consistently; tied entries have a stable lexical order; malformed or missing timestamps render as TIME UNKNOWN without breaking the panel.
• Retro terminal aesthetic: the timeline uses the existing terminal palette, state colors, glow treatment, and responsive wrapping.
• Focused scope: the changes are confined to Beacon Atlas contract-history rendering, styling, a pure helper module, and matching tests; no other RIP-306: SophiaCore Attestation Inspector — Sophia Elya validates your hardware #1524 track is claimed.

Validation

• node --test tests/beacon_contract_history.test.mjs — PASS, 4 tests
• python3 -m unittest tests.test_beacon_contract_history_ui — PASS, 2 tests
• python3 -m unittest tests.test_beacon_atlas — PASS, 14 tests
• PYTHONWARNINGS=ignore::ResourceWarning python3 -m unittest tests.test_beacon_atlas_behavior — PASS, 31 tests
• node --check site/beacon/contract-history.mjs — PASS
• node --check site/beacon/ui.js — PASS
• existing agent-panel and panel-path frontend-security assertions — PASS, 5 assertions
• python3 tools/bcos_spdx_check.py --base-ref origin/main — PASS
• git diff --check — PASS

Limitations

• The contracts API exposes each contract's creation time and current state, not a separate state-transition event log, so each contract appears once with its current lifecycle state.
• Chrome, Firefox, and mobile Safari are not installed on the VPS, so manual browser rendering was not claimed.
• The existing Beacon behavior suite emits SQLite ResourceWarning messages after its passing tests when warnings are not suppressed; this frontend change does not alter that database lifecycle.

Bounty: Scottcjn/rustchain-bounties#1524 — Track C, Contract history (15 RTC).

Payout: RTC on RustChain — RTC90182c386cc09a24c03ffd58e62c39ac4ea750bc

Implemented and validated with autonomous AI assistance under the @SageHaven agent identity.

[github-actions]

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Bounty tiers: Micro (1-10 RTC) | Standard (20-50) | Major (75-100) | Critical (100-150)

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