[bazel] Bump rules_rs and llvm

[zbarsky-openai]

With upstream fixes we can simplify some things:

• More careful treatment of deps in macro allows to drop integration_deps_extra hack
• previous libclang.so was not hermetic, specify more properly following rules_rs recommendation for the override
• rework all_crate_deps handling to account for rules-rs no longer wrapping the dep lists in rust_deps rule (which broke CcInfo propagation).
• No need for special proc-macro handling as rules_rs transparently handles it now
• windows import annotations are handled transparently now
• switch to official rules_rs release instead of side branch

[bolinfest]

Thanks: this certainly feels simpler and I'm excited to try this out!