Add deployment history log to the editor #16

Summary

After deploying a contract, users have no record of what was deployed, to which network, when, or how the on-chain transaction resolved. This issue builds a full deployment history system with persistent storage, Stellar Explorer deep-links, transaction status polling, and the ability to re-inspect a past deployment in the contract inspector.

Why This Is Hard

• Transaction status is async: at the moment of a successful deployContract() call the transaction may still be PENDING on-chain. The history system must store the initial record immediately, then poll GET /transaction/:hash in the background and update the record when the status resolves to SUCCESS or FAILED.
• Storage schema versioning: localStorage is long-lived. The schema for deployment records will evolve. The system must include a schema version field and a migration function so records written today still load correctly after future updates.
• Re-inspection link: each history entry must link back to /inspect/[contractId] (see issue Build a read-only contract inspector / viewer #18) — but the inspector needs the network context, so the history record must persist the network alongside the contract ID.
• WASM hash tracking: the record should store the sourceHash from the compile response so users can verify which graph version produced a given deployment. This requires passing sourceHash from compileContract() all the way through to deployContract() and up to the history writer.
• Data integrity: history records contain sensitive-ish data (wallet address, contract IDs). The size of localStorage is bounded (~5 MB). The system must cap records at a configurable max (default: 50) and evict oldest-first when the cap is reached.

Proposed Design

Storage layer (src/lib/editor/deploymentHistory.ts)

export type DeploymentStatus = "pending" | "success" | "failed"

export interface DeploymentRecord {
  id: string                   // uuid
  version: 1                   // schema version
  timestamp: number            // Date.now() at submission
  network: StellarNetwork
  contractId: string
  txHash: string | null
  status: DeploymentStatus
  sourceHash: string           // from CompileResponse.sourceHash
  walletAddress: string
  graphNodeCount: number
}

export function appendDeploymentRecord(record: Omit<DeploymentRecord, "id" | "version">): DeploymentRecord
export function loadDeploymentHistory(): DeploymentRecord[]
export function updateDeploymentStatus(id: string, status: DeploymentStatus): void
export function deleteDeploymentRecord(id: string): void
export function clearDeploymentHistory(): void

Records are stored as a JSON array under lumens-block:deployments. Cap at 50 entries; evict oldest on overflow.

Status poller (src/lib/stellar/txPoller.ts)

export function pollTransactionStatus(
  txHash: string,
  network: StellarNetwork,
  onResult: (status: "success" | "failed") => void,
  options?: { intervalMs?: number; maxAttempts?: number }
): () => void   // returns a cancel function

• Polls SorobanRpc.Server.getTransaction(txHash) every 2 seconds.
• Stops after 60 attempts (2 minutes) and marks the record as "failed" on timeout.
• Returns a cancel function that clears the interval — must be called on component unmount.

DeploymentHistory component (src/components/editor/DeploymentHistory.tsx)

• Slide-out drawer (right-side, 380 px), opened by a History button in the Toolbar.
• Each record shows:
  • Status icon: spinner (pending), green tick (success), red X (failed)
  • Relative timestamp ("2 minutes ago") via Intl.RelativeTimeFormat
  • Network badge (Testnet / Mainnet)
  • Truncated contract ID + copy button
  • Tx hash truncated + Stellar Expert link (correct network URL)
  • Graph size ("7 nodes")
  • Inspect button → navigates to /inspect/[contractId]?network=[network]
  • Delete button (trash icon, confirm on click)
• Empty state: "No deployments yet. Deploy a contract to see it here."
• Clear All button at the bottom, gated by a confirmation dialog.

Integration (DeployButton.tsx)

After deployContract() resolves:

1. Call appendDeploymentRecord(...) with the result.
2. Call pollTransactionStatus(txHash, network, (status) => updateDeploymentStatus(id, status)).
3. Store the cancel function and call it on component unmount.

Acceptance Criteria

• DeploymentRecord schema includes all required fields plus version: 1.
• Records are persisted to localStorage and survive page refresh.
• The record cap (50 entries) is enforced; oldest entry is evicted when exceeded.
• pollTransactionStatus updates a pending record to success or failed after the transaction resolves.
• The poller is cancelled on component unmount (no memory leak).
• The history drawer shows the correct status icon (spinner / tick / X) per record.
• Contract ID and tx hash are copyable with a single click (copy-to-clipboard + "Copied!" tooltip).
• Stellar Expert links open https://stellar.expert/explorer/[network]/tx/[hash] on the correct network.
• Inspect button navigates to /inspect/[contractId]?network=[network].
• Individual records and all records can be deleted with a confirmation step.
• Unit tests cover: appendDeploymentRecord cap enforcement, updateDeploymentStatus correctness, pollTransactionStatus resolve and timeout paths.
• A Playwright E2E test: mocks a deploy response, asserts the history drawer shows a new pending record, then asserts it updates to success after the mock poller fires.
• All existing tests pass.