Remove `EntityDb`, inlining it into `StoreDb` #6280

Job	Run time
cpp-paths-filter	7s
Checks / Python lints (ruff, mypy, …)	2m 12s
Checks / Test Python Docs	26s
Checks / Check if running codegen would produce any changes	1m 59s
Checks / Rust lints (fmt, check, cranky, tests, doc)	1m 28s
Checks / Check Rust web build (wasm32 + wasm-bindgen)	1m 48s
Checks / Lint TOML files	17s
Checks / Rerun lints	2m 7s
Checks / Spell Check	4s
Checks / Cargo Deny	2m 2s
Checks / C++ formatting check	2m 14s
Checks / Misc formatting	18s
Minimum Wheel Build / Set Config (linux)	4s
Build JS / Build	2m 10s
Build & Upload rerun-cli (Linux x64) / Set Config (linux)	2s
Build Web / Build Web (wasm32 + wasm-bindgen)	2m 14s
Build & Upload rerun_c (Linux x64) / Set Config (linux)	2s
Update PR Body / Update PR body	1m 52s
Build & Upload rerun_c (Linux x64) / Build rerun_c (ubuntu-latest-16-cores)	2m 7s
C++ tests / matrix_prep	3s
Build & Upload rerun-cli (Linux x64) / Build rerun-cli (ubuntu-latest-16-cores)	1m 21s
Minimum Wheel Build / Build Wheels (ubuntu-latest-16-cores)	56s
C++ tests / C++ build & test - Linux x64	1m 25s
Minimum Wheel Test	0s
Build Examples	0s
Run Notebook	0s
Track Sizes	0s
Upload Examples	0s
Bundle and upload rerun_cpp_sdk.zip	0s
Upload Web	0s
Save PR Summary	0s
	27m 18s

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