Coordinate pagefind search rollout

[ritorhymes]

Built on top of the V2 multi-repo local build system tracked in #15.

Description

This tracks the Pagefind search rollout across the preprocessor and theme repos.

The rollout replaces the existing Fuse-based browser search with a Pagefind-backed build output and theme UI. The preprocessor generates the search route configuration, runs Pagefind indexing for build output, exposes the proposal metadata contracts needed by search, and can emit a rendered HTML search corpus for debugging and external consumers such as supporting semantic search systems. The theme renders the search route, exposes the Pagefind indexing hooks on proposal pages, replaces the quick search runtime, and adds the full search page with URL-backed filters, sorting, pagination, Created Date filtering, share links, and 24-hour last-search restore.

Pagefind indexing is generated as part of build output only. This rollout does not add live indexing to serve or check, which would require separate lifecycle handling.

Demo site: wg-eips.ritovision.com

Addresses:

• Investigate search options besides fuse.js #5

PR Sequence

Prerequisite

• Generate Proposal Metadata JSON #34 — Generate Proposal Metadata JSON

Preprocessor (stacked on #34, merge in order)

• 1/3 Add Pagefind backend indexing and search route #40 — Add Pagefind backend indexing and search route
• 2/3 Expose search metadata contracts #41 — Expose search metadata contracts
• 3/3 Add rendered search corpus output #42 — Add rendered search corpus output

Theme (depends on the generated search config and Pagefind output)

• 1/6 Add search route templates and Pagefind hooks theme#19 — Add search route templates and Pagefind hooks
• 2/6 Add Pagefind search runtime core theme#20 — Add Pagefind search runtime core
• 3/6 Add full search filter controls theme#21 — Add full search filter controls
• 4/6 Add Created Date search filter theme#22 — Add Created Date search filter
• 5/6 Add full search pagination theme#23 — Add full search pagination
• 6/6 Add search restore and UI validation theme#24 — Add search restore and UI validation

Post-rollout Follow-up

Search and Network Upgrade Integration

• Open a final follow-up PR after the search stack and hardfork/network-upgrade stack are ready to integrate.
• Use that PR to layer hardfork/network-upgrade search behavior onto the completed Pagefind search UI rather than mixing that work into the base search rollout.