fix: expose upstream ai errors as not 500s

[Salazareo]

No description provided.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	70.65% ⬇️ -0.06%	12896 / 18253
🔵	Statements	69.15% ⬇️ -0.08%	13621 / 19695
🔵	Functions	69.89% ⬆️ +0.06%	2152 / 3079
🔵	Branches	58.59% ⬇️ -0.10%	8557 / 14603

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
src/backend/server.ts	50.13% ⬇️ -0.94%	35.49% ⬇️ -1.12%	43.58% 🟰 ±0%	51.11% ⬇️ -0.87%	87-88, 102-107, 122-128, 173-186, 213-221, 244-245, 248-257, 260-264, 272, 275, 278, 284, 307, 314-320, 323-374, 397-425, 442-470, 484-486, 505-509, 532, 547-549, 559-564, 567-573, 576-582, 585-591, 601-603, 614, 618-620, 635, 641-677, 690-710, 717-718, 749-786
src/backend/controllers/drivers/DriverController.ts	71.92% ⬇️ -8.08%	37.98% ⬇️ -5.18%	56.75% ⬇️ -1.58%	78.52% ⬇️ -9.59%	6, 13, 16, 24-26, 32-34, 38-39, 43, 44, 45, 46, 47, 126-158, 181, 274-276, 296, 308, 311-316, 359-361, 366, 368-371
src/backend/core/http/middleware/errorHandler.ts	85.41% ⬇️ -11.36%	75.51% ⬇️ -20.49%	80% ⬆️ +5.00%	86.95% ⬇️ -9.71%	68-71, 85, 128-130, 133, 144-146, 150-152, 166-168
src/backend/drivers/ai-chat/ChatCompletionDriver.ts	77.36% ⬆️ +0.08%	68.98% ⬇️ -0.06%	93.33% ⬆️ +2.03%	79.02% ⬆️ +0.17%	96, 135-138, 142-145, 148-151, 154-157, 164-167, 179-182, 233, 247, 254, 256, 286, 300, 333-335, 416-420, 448-477, 537-543, 625, 649, 655, 777-785, 790-812, 824-827, 832-835, 840-843, 856-859, 865-871, 877-883, 888-891, 908-914, 944, 949-974, 984-993, 1002-1012, 1031
src/backend/drivers/ai-tts/providers/elevenlabs/ElevenLabsTTSProvider.ts	100% 🟰 ±0%	84.12% ⬇️ -4.76%	100% 🟰 ±0%	100% 🟰 ±0%
src/backend/services/health/ServerHealthService.ts	42.01% ⬆️ +0.35%	32.6% 🟰 ±0%	36.36% 🟰 ±0%	45.04% ⬆️ +0.40%	94-103, 123-124, 135, 140-150, 167-170, 184-195, 206-208, 216-219, 227-286, 290, 292, 307-317

Generated in workflow #201 for commit 342130c by the Vitest Coverage Report Action