[main][Docs] Fix typos across documentation (#6728)

## Summary

Fix typos and improve grammar consistency across 50 documentation files.
 
### Changes include:
- Spelling corrections (e.g., "Facotory" → "Factory", "certainty" →
"determinism")
- Grammar improvements (e.g., "multi-thread" → "multi-threaded",
"re-routed" → "re-run")
- Punctuation fixes (semicolon consistency in filter parameters)
- Code style fixes (correct flag name `--num-prompts` instead of
`--num-prompt`)
- Capitalization consistency (e.g., "python" → "Python", "ascend" →
"Ascend")
- vLLM version: v0.15.0
- vLLM main:
9562912cea

---------

Signed-off-by: SlightwindSec <slightwindsec@gmail.com>

benchmarks/README.md

@@ -145,7 +145,7 @@ These files contain detailed benchmarking results for further analysis.
 #### Use benchmark cli
 
 For more flexible and customized use, benchmark cli is also provided to run online/offline benchmarks
-Similarly, let’s take `Qwen2.5-VL-7B-Instruct` benchmark as an example:
+Similarly, let's take `Qwen2.5-VL-7B-Instruct` benchmark as an example:
 
 ##### Online serving