docs: update install instructions to use PyPI package name (#15)

lmcache-turbo-quant-serde 0.1.0 is now live on PyPI; replace the
dev-install one-liners with the published pip commands in both the
integration README and the main README LMCache section.

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: pbertsch

README.md

@@ -403,7 +403,8 @@ Standalone HTML: [`reports/benchmark_report.html`](reports/benchmark_report.html
 remote DRAM) are compressed to ~26% of their fp16 size with Δppl = 0.00.
 
 ```bash
-pip install -e integrations/lmcache   # until published to PyPI
+pip install lmcache-turbo-quant-serde          # includes tqai automatically
+pip install lmcache-turbo-quant-serde[lmcache] # + LMCache v1 engine
 ```
 
 ```python

integrations/lmcache/README.md

@@ -13,8 +13,8 @@ required.
 ## Quick start
 
 ```bash
-pip install tqai
-pip install -e integrations/lmcache   # until published to PyPI
+pip install lmcache-turbo-quant-serde          # includes tqai automatically
+pip install lmcache-turbo-quant-serde[lmcache] # + LMCache v1 engine
 ```
 
 ```python