static plugin: setting urlPath prevents all files from being served (5.1.15) #1583

Bug Summary

Configuring the built-in static plugin with the documented urlPath option results in no files being served at all — every candidate URL returns 404. Removing urlPath (same files, same glob) serves correctly.

Steps to Reproduce

Minimal component (two files):

static-min/
├── config.yaml
└── web/
    └── test.css

config.yaml:

static:
  files: 'web/**'
  urlPath: 'assets'

1. harper dev .
2. curl -i http://localhost:9926/assets/test.css → 404
3. Also 404: /test.css, /assets/web/test.css, /web/test.css (no candidate path serves)

Control cases on the same instance:

• config.yaml with only static: { files: 'web/**' } → GET /test.css → 200 ✅
• No config.yaml at all (default config) → GET /test.css → 200 ✅

So the regression is isolated to the presence of urlPath.

Expected Behavior

Per the Static Files docs (files and urlPath section): with urlPath: 'assets', GET /assets/test.css should return web/test.css.

Actual Behavior

404 for every path; no error or warning in the log (level warn). At debug level the only nearby output is Initial scan complete, still waiting for N pending file reads. Files added to web/ after startup are also never served, so the plugin's file map appears to stay empty (or is keyed differently than the request handler's staticFiles.get(req.pathname) lookup in server/static.ts expects). resolveBaseURLPath('…', 'assets') → /assets/ and deriveURLPath → /assets/test.css look correct in isolation, so the suspect is the entry pipeline when urlPath is set rather than the URL derivation itself.

Environment

• Harper 5.1.15 (npm global install)
• Node v24.16.0, macOS (darwin 25.5.0, arm64)
• Reproduced under both harper dev and a fresh install's harper start

Workaround

Nest the files so the glob-base strip produces the prefix instead: move files to web/assets/… and use static: { files: 'web/**' } with no urlPath — files then serve at /assets/….

Context

Found while dogfooding the docs-site replatform (serving docs.harperdb.io from Harper).