Use Retrieval Skill for Adding Files to Agents

[tmichaeldb]

Requires this PR to be merged.

Now that we support our new retrieval skill, we should use that by default

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
mindsdb_sdk
agents.py	122	45	63%	20, 79, 87, 90, 94, 96, 98, 100, 102, 168–206, 229–231, 252–254, 258–262
databases.py	42	2	95%	107, 134
handlers.py	39	1	97%	77
jobs.py	97	7	93%	41, 53, 81, 85, 147–150
knowledge_bases.py	124	16	87%	58–61, 125, 145, 149–156, 161–165, 244–247, 316, 333
ml_engines.py	42	3	93%	94, 126, 128
models.py	211	19	91%	109, 140–141, 222, 231, 233, 303, 339, 348, 372, 403, 497, 505, 524, 540, 548, 573, 577, 590
projects.py	63	1	98%	167
query.py	13	1	92%	14
skills.py	53	7	87%	43, 45, 49, 59, 76–80, 122
tables.py	130	15	88%	140–142, 145, 165, 192, 203–204, 209, 224, 227, 321, 342–347, 356, 376
views.py	37	2	95%	105, 138
mindsdb_sdk/connectors
rest_api.py	179	31	83%	16–26, 32–33, 48, 69–71, 92, 95, 102–105, 156–164, 330–340
TOTAL	1240	150	88%

Tests	Skipped	Failures	Errors	Time
14	0 💤	0 ❌	0 🔥	8.934s ⏱️

[ea-rus]

This PR is refering to https://github.com/mindsdb/mindsdb/pull/9119/files
But in SDK PR I see only changes in KB skill and don't see anything about it in mindsdb PR
They are really dependent?