Adopt path-based server function addressing

[ryansolid]

Summary

Downstream adoption of solidjs/solid#3076, which moved the server function id into the path (<endpoint>/<id>) and retired both the X-Server-Function-Id header and the ?id= query fallback.

• The generic form-action fallback (createServerFormAction) reads the id back through the runtime's new parseServerFunctionUrl instead of parsing ?id= by hand — the router no longer hard-codes the addressing scheme.
• Bound ?args composition (action.with) is untouched: arguments stayed in the query per the #3072 discussion, and hashKey already emits the plain JSON the server-side convention decodes.
• "Not an address" now means a malformed path (bare endpoint, extra segments) rather than a missing ?id; the native-submission fallbacks keep working through the runtime's parse answering null.
• actionBase prefix interception is unchanged — /_server/<id> still lives under /_server.

Draft until

@solidjs/web publishes the addressing change (anything newer than 2.0.0-rc.3). The ^2.0.0-rc.3 range picks the new build up on publish; CI here will fail on the missing parseServerFunctionUrl export until then.

Test plan

• Full suite (dom + server configs + type tests) passes locally against a file: link to the @solidjs/web build from solid next — 382 + 33 passing.
• Re-run CI once the next @solidjs/web prerelease is published.

Made with Cursor

[changeset-bot]

🦋 Changeset detected

Latest commit: 31ea11b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@solidjs/router	Patch

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[ryansolid]

Companion plugin PR: solidjs/solid-vite-plugin#332 (endpoint prefix-matching + path-based module preload in the dev middleware). Both are draft until the next @solidjs/web prerelease publishes the addressing change.