feat(zcash): add blocks list and block detail pages

[MatiasOS]

Description

Adds the Zcash blocks list (/zec/blocks) and block detail (/zec/block/:filter) pages, plus their tzec equivalents.

• Blocks list: costs one getblock call per block. Rows fill in as each call returns, so the page stays usable on rate-limited gateways. Pagination uses ?fromBlock, the same as Bitcoin.
• Block page: everything comes from a single getblock(height, 2) call. It shows:
  • Zcash-specific header fields: the hex nonce, the Equihash solution, block commitments, the final Sapling and Orchard roots, and note commitment tree sizes (including Ironwood).
  • Coinbase outputs.
  • The number of shielded transactions in each pool.
  • The value pools after this block.

Related Issue

Part of #398. Stacked on #407.

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactoring
• Performance improvement
• Other (please describe):

Changes Made

• ZcashBlocksPage, ZcashBlockPage and ZcashBlockDisplay.
• ZcashValuePools now takes the pools directly, so the block page can reuse it.
• Routes and lazy exports for zec|tzec/blocks and zec|tzec/block/:filter.
• zcash locale strings and tooltips.zcash.block in all 5 locales.
• Styles for the pool chips, coinbase outputs and the Equihash solution row.
• A hermetic e2e spec at e2e/tests/shared/mocked/zcash-blocks.spec.ts.

Screenshots (if applicable)

Checked locally against mocked RPC data at desktop width and at 400px.

Checklist

• I have run npm run format:fix and npm run lint:fix
• I have run npm run typecheck with no errors
• I have run tests with npm run test:run
• I have tested my changes locally
• I have updated documentation if needed
• My code follows the project's architecture patterns

Additional Notes

• There are no per-block fee totals. Zebra doesn't return transparent input values, so a block total would need a lookup for every input. Per-transaction fees are handled on the transaction page, in the next PR.
• The coinbase address, transaction and address links point to pages that later PRs in the stack add.
• In dev, React StrictMode can send the block request twice. The e2e spec therefore checks which blocks are requested rather than how many requests are made.
• Tests:
  • npm run test:run: 150 passing.
  • Hermetic Zcash e2e specs (dashboard and blocks): 4 passing.