chore: update to rust 1.93.1, enable a few more clippy lints

[MingweiSamuel]

i love lints

Mainly manual_let_else, needless_for_each, others

[Copilot]

Pull request overview

Enables additional workspace-level Clippy lints and updates a handful of call sites to satisfy the new lint set (primarily manual_let_else, needless_for_each, and manual_string_new), improving code consistency and lint signal across the repo.

Changes:

• Enabled several additional Clippy lints in [workspace.lints.clippy].
• Refactored a set of if let/match patterns into let ... else and for_each into for loops.
• Replaced "...".to_owned() empty-string constructions with String::new() in a few places.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
Cargo.toml	Enables additional Clippy lints at the workspace level.
lattices/src/algebra.rs	Updates tests to use String::new() for empty strings.
hydro_test/examples/http_hello.rs	Uses let ... else for extracting TCP port.
hydro_test/examples/http_counter.rs	Uses let ... else for extracting TCP port.
hydro_lang/src/viz/json.rs	Uses let ... else to destructure JSON objects.
hydro_lang/src/sim/graph.rs	Replaces for_each chains with for loops.
hydro_lang/src/sim/compiled.rs	Replaces for_each with for loops over hooks.
hydro_lang/src/sim/builder.rs	Uses String::new() in fallback location tuple.
hydro_lang/src/location/cluster.rs	Uses let ... else to destructure LocationId.
hydro_lang/src/deploy/deploy_runtime_containerized.rs	Logs the result when handshake frames are missing/fail.
hydro_lang/src/deploy/deploy_graph_containerized_ecs.rs	Uses let ... else to destructure LocationId.
hydro_lang/src/compile/ir/mod.rs	Replaces for_each with for loops for traversal.
benches/benches/futures.rs	Refactors a boolean match into if/else in poll.

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[Copilot]

Pull request overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 3 comments.

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