[LevK]: Build and test as a standalone package

Split out of actions/toolkit (packages/http-client, history kept by filter-repo).
Brings the 2024 [LevK] packaging edits forward onto current upstream:

- tsconfig.json: the monorepo root's compiler options inlined, no extends
- jest.config.cjs: the root's ts-jest transform, rooted at tests/
  (isolatedModules: ESM lib/ and sources run through CommonJS)
- __tests__/ -> tests/
- package.json: test = jest, build = tsc; jest/ts-jest/typescript as
  devDependencies; repository, homepage, bugs on git.levk.dev
- .gitignore: node_modules/, lib/, audit.json
- HttpCodes.PayloadTooLarge = 413 (the 2024 edit; still missing upstream)

Not carried over from 2024: the _getExistingOrDefaultHeader type
narrowing (upstream has since fixed it properly), version reset to 1.0.0 (dependents' ranges
need upstream's numbering) and the Unlicense field (the code is MIT).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHXzGrsxfkGk8LmwrBbHNZ

tests/auth.test.ts

@@ -0,0 +1,72 @@
+import * as httpm from '../lib'
+import * as am from '../lib/auth'
+
+describe('auth', () => {
+  beforeEach(() => {})
+
+  afterEach(() => {})
+
+  it('does basic http get request with basic auth', async () => {
+    const bh: am.BasicCredentialHandler = new am.BasicCredentialHandler(
+      'johndoe',
+      'password'
+    )
+    const http: httpm.HttpClient = new httpm.HttpClient('http-client-tests', [
+      bh
+    ])
+    const res: httpm.HttpClientResponse = await http.get(
+      'https://postman-echo.com/get'
+    )
+    expect(res.message.statusCode).toBe(200)
+    const body: string = await res.readBody()
+    const obj = JSON.parse(body)
+    const auth: string = obj.headers.authorization
+    const creds: string = Buffer.from(
+      auth.substring('Basic '.length),
+      'base64'
+    ).toString()
+    expect(creds).toBe('johndoe:password')
+    expect(obj.url).toBe('https://postman-echo.com/get')
+  })
+
+  it('does basic http get request with pat token auth', async () => {
+    const token = 'scbfb44vxzku5l4xgc3qfazn3lpk4awflfryc76esaiq7aypcbhs'
+    const ph: am.PersonalAccessTokenCredentialHandler =
+      new am.PersonalAccessTokenCredentialHandler(token)
+
+    const http: httpm.HttpClient = new httpm.HttpClient('http-client-tests', [
+      ph
+    ])
+    const res: httpm.HttpClientResponse = await http.get(
+      'https://postman-echo.com/get'
+    )
+    expect(res.message.statusCode).toBe(200)
+    const body: string = await res.readBody()
+    const obj = JSON.parse(body)
+    const auth: string = obj.headers.authorization
+    const creds: string = Buffer.from(
+      auth.substring('Basic '.length),
+      'base64'
+    ).toString()
+    expect(creds).toBe(`PAT:${token}`)
+    expect(obj.url).toBe('https://postman-echo.com/get')
+  })
+
+  it('does basic http get request with pat token auth', async () => {
+    const token = 'scbfb44vxzku5l4xgc3qfazn3lpk4awflfryc76esaiq7aypcbhs'
+    const ph: am.BearerCredentialHandler = new am.BearerCredentialHandler(token)
+
+    const http: httpm.HttpClient = new httpm.HttpClient('http-client-tests', [
+      ph
+    ])
+    const res: httpm.HttpClientResponse = await http.get(
+      'https://postman-echo.com/get'
+    )
+    expect(res.message.statusCode).toBe(200)
+    const body: string = await res.readBody()
+    const obj = JSON.parse(body)
+    const auth: string = obj.headers.authorization
+    expect(auth).toBe(`Bearer ${token}`)
+    expect(obj.url).toBe('https://postman-echo.com/get')
+  })
+})