Setup ephemeral PDS server for testing

[shuuji3]

The current setup uses the real accounts (@alice.bsky.social and @bob.bsky.social) for testing. But sometimes it causes the rate limit errors, especially when iterating changes during the local development.

Probably we can take a same setup as atcute's internal dev-env: https://github.com/mary-ext/atcute/blob/trunk/packages/internal/dev-env/lib/pds.ts

Example of the rate limit error message:

> CI=1 pnpm -r test:coverage
Scope: 4 of 5 workspace projects
packages/client test:coverage$ vitest --coverage
packages/client test:coverage:  RUN  v2.1.6 /home/shuuji3/dev/tsky/packages/client
packages/client test:coverage:       Coverage enabled with istanbul
packages/client test:coverage:  ❯ src/bsky/feed/feed.test.ts (1 test | 1 failed) 558ms
packages/client test:coverage:    × feed > .getFeed() 557ms
packages/client test:coverage:      → RateLimitExceeded > Rate Limit Exceeded
packages/client test:coverage:  ✓ src/user/profile.test.ts (3 tests) 1348ms
packages/client test:coverage:    ✓ profile > Getting alice's profile 630ms
packages/client test:coverage:    ✓ profile > Getting bob's profile 483ms
packages/client test:coverage:  ✓ src/user/preferences/preferences.test.ts (2 tests) 2155ms
packages/client test:coverage:    ✓ preferences > .get() 1201ms
packages/client test:coverage:    ✓ preferences > .set() 954ms
packages/client test:coverage: ⎯⎯⎯⎯⎯⎯⎯ Failed Tests 1 ⎯⎯⎯⎯⎯⎯⎯
packages/client test:coverage:  FAIL  src/bsky/feed/feed.test.ts > feed > .getFeed()
packages/client test:coverage: XRPCError: RateLimitExceeded > Rate Limit Exceeded
packages/client test:coverage:  ❯ XRPC.request ../../node_modules/.pnpm/@atcute+client@2.0.6/node_modules/@atcute/client/lib/rpc.ts:182:10
packages/client test:coverage:  ❯ CredentialManager.login ../../node_modules/.pnpm/@atcute+client@2.0.6/node_modules/@atcute/client/lib/credential-manager.ts:262:15
packages/client test:coverage:  ❯ Auth.login src/auth/auth.ts:26:3
packages/client test:coverage:      24| 
packages/client test:coverage:      25|     return session;
packages/client test:coverage:      26|   }
packages/client test:coverage:        |   ^
packages/client test:coverage:      27| 
packages/client test:coverage:      28|   async switch(did: string) {
packages/client test:coverage:  ❯ getAliceTsky src/bsky/feed/feed.test.ts:20:3
packages/client test:coverage:  ❯ src/bsky/feed/feed.test.ts:30:18
packages/client test:coverage: ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[1/1]⎯
packages/client test:coverage:  Test Files  1 failed | 2 passed (3)
packages/client test:coverage:       Tests  1 failed | 5 passed (6)
packages/client test:coverage:    Start at  16:27:06
packages/client test:coverage:    Duration  2.70s (transform 275ms, setup 0ms, collect 1.43s, tests 4.06s, environment 0ms, prepare 162ms)
packages/client test:coverage:  % Coverage report from istanbul
packages/client test:coverage: ------------------|---------|----------|---------|---------|-------------------
packages/client test:coverage: File              | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
packages/client test:coverage: ------------------|---------|----------|---------|---------|-------------------
packages/client test:coverage: All files         |   12.77 |    10.63 |   13.46 |   12.84 |                   
packages/client test:coverage:  auth             |   54.54 |       50 |      60 |   54.54 |                   
packages/client test:coverage:   auth.ts         |   54.54 |       50 |      60 |   54.54 | 29-39             
packages/client test:coverage:  bsky             |       0 |      100 |       0 |       0 |                   
packages/client test:coverage:   bsky.ts         |       0 |      100 |       0 |       0 | 7-18              
packages/client test:coverage:  bsky/actor       |   16.66 |        0 |   13.33 |   16.66 |                   
packages/client test:coverage:   actor.ts        |   16.66 |        0 |   13.33 |   16.66 | 33-139            
packages/client test:coverage:  bsky/feed        |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   feed.ts         |       0 |        0 |       0 |       0 | 11-49             
packages/client test:coverage:   generator.ts    |       0 |        0 |       0 |       0 | 11-73             
packages/client test:coverage:  bsky/list        |       0 |      100 |       0 |       0 |                   
packages/client test:coverage:   list.ts         |       0 |      100 |       0 |       0 | 7-43              
packages/client test:coverage:  bsky/post        |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   post.ts         |       0 |        0 |       0 |       0 | 13-106            
packages/client test:coverage:  starterpack      |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   starterpack.ts  |       0 |        0 |       0 |       0 | 10-61             
packages/client test:coverage:  tsky             |   53.33 |       25 |   55.55 |   53.33 |                   
packages/client test:coverage:   client.ts       |      75 |      100 |      75 |      75 | 54                
packages/client test:coverage:   tsky.ts         |   45.45 |       25 |      40 |   45.45 | 25,32-44          
packages/client test:coverage:  user             |    9.09 |        0 |   11.11 |    9.09 |                   
packages/client test:coverage:   index.ts        |    9.09 |        0 |   11.11 |    9.09 | 23-63             
packages/client test:coverage:  user/mute        |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   mute.ts         |       0 |        0 |       0 |       0 | 5-32              
packages/client test:coverage:  user/muted       |       0 |      100 |       0 |       0 |                   
packages/client test:coverage:   muted.ts        |       0 |      100 |       0 |       0 | 6-38              
packages/client test:coverage:  user/preferences |     100 |      100 |     100 |     100 |                   
packages/client test:coverage:   preferences.ts  |     100 |      100 |     100 |     100 |                   
packages/client test:coverage:  user/suggestion  |       0 |      100 |       0 |       0 |                   
packages/client test:coverage:   suggestion.ts   |       0 |      100 |       0 |       0 | 6-47              
packages/client test:coverage:  user/unmute      |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   unmute.ts       |       0 |        0 |       0 |       0 | 5-32              
packages/client test:coverage:  utils            |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   paginator.ts    |       0 |        0 |       0 |       0 | 6-47              
packages/client test:coverage:  video            |       0 |        0 |       0 |       0 |                   
packages/client test:coverage:   video.ts        |       0 |        0 |       0 |       0 | 6-85              
packages/client test:coverage: ------------------|---------|----------|---------|---------|-------------------
packages/client test:coverage: Failed
/home/shuuji3/dev/tsky/packages/client:
 ERR_PNPM_RECURSIVE_RUN_FIRST_FAIL  @tsky/client@0.0.1 test:coverage: `vitest --coverage`
Exit status 1