Issue 17643 runtime reproduction, 2026-10-22 UTC
Host: Linux fs-04; current main 8d3b061121
Runtime: vp install; vp run dev --no-seed; real HTTP server at loopback port 14917.
Isolated worktree .t3/userdata/statev2.sqlite; synthetic projection inserted, no live database accessed.
Thread ID: thread:delegated-task:command%3Amcp%3Aissue-17643
No provider execution needed: the defect is retrieving an existing child thread.
Browser-session authentication succeeded (HTTP 200); credential excluded.
Protocol header: x-t3-orchestration-protocol: 2

Correct single-encoded request:
GET /api/orchestration/threads/thread:delegated-task:command%253Amcp%253Aissue-17643/bounded
HTTP 200
projection.thread.id = thread:delegated-task:command%3Amcp%3Aissue-17643

Reported double-encoded request:
GET /api/orchestration/threads/thread:delegated-task:command%25253Amcp%25253Aissue-17643/bounded
HTTP 404
{"_tag":"EnvironmentResourceNotFoundError","code":"not_found","reason":"thread_not_found"}

This reproduces the server consequence of the two request paths, not execution of the Swift client.
Swift source branch: t3code/rebuild-mobile-app-swift at 4619c0bca6.
Swift client execution, Swift tests, and native before/after recordings are unverified: no Swift compiler or Xcode on this Linux VM.
cannot-verify ios-swift
Server stopped after reproduction; loopback ports confirmed released.