fix: clarify loader delay validation

[Teagan42]

What

• prevent negative loader delays via the CLI and runtime guard
• add regression tests covering CLI and programmatic usage, including explicit CLI exit-code assertions
• clarify the runtime error message and bump the project version to 2.0.6

Why

• negative delays previously crashed in asyncio.sleep; these guards catch the issue earlier with a clear error

Affects

• loader CLI delay option and the load_media orchestrator

Testing

• uv run ruff check .
• uv run pytest

Documentation

• not needed

---

https://chatgpt.com/codex/tasks/task_e_68e4d78f5a148328869c977933c65a02

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
mcp_plex/common
types.py	166	1	99%	168
validation.py	28	2	93%	37–38
mcp_plex/loader
__init__.py	179	15	92%	89–96, 138, 205, 320–322, 324, 410–429
__main__.py	4	4	0%	2–8
imdb_cache.py	43	2	95%	59, 63
qdrant.py	198	2	99%	335–340
samples.py	41	3	93%	54–56
mcp_plex/loader/pipeline
channels.py	64	2	97%	134–135
enrichment.py	520	75	86%	240, 263–269, 322, 327, 358, 360, 367, 371, 475, 496, 516, 524–526, 529–531, 534–536, 544–549, 557, 611–612, 636, 696–697, 713, 742, 749, 751, 755, 807, 825, 837, 866, 872, 875–883, 909, 912–914, 931–933, 953–956, 960, 974–980, 1002, 1004, 1007–1009
ingestion.py	155	13	92%	81, 130–150, 185, 222, 238, 331, 337, 357
orchestrator.py	95	5	95%	63, 141, 170, 193–194
persistence.py	130	9	93%	122, 164–165, 175, 186, 190–192, 245
mcp_plex/server
__init__.py	351	28	92%	55–56, 136–137, 185, 202, 240, 261–264, 278–281, 289, 363, 366, 404, 422–423, 461, 491, 509, 515, 533, 632–634, 638
__main__.py	4	4	0%	3–8
cli.py	62	1	98%	73
config.py	82	12	85%	58, 61–69, 76, 82, 102, 116
media.py	85	4	95%	62, 84–85, 95
mcp_plex/server/tools
media_library.py	289	11	96%	477, 760, 783–791
TOTAL	2697	193	93%

Tests	Skipped	Failures	Errors	Time
159	0 💤	0 ❌	0 🔥	1m 19s ⏱️