proxy: Enable stricter/pedantic clippy checks (#8775)

Create a list of currently allowed exceptions that should be reduced
over time.

proxy/src/lib.rs

@@ -1,4 +1,92 @@
-#![deny(clippy::undocumented_unsafe_blocks)]
+// rustc lints/lint groups
+// https://doc.rust-lang.org/rustc/lints/groups.html
+#![deny(
+    deprecated,
+    future_incompatible,
+    // TODO: consider let_underscore
+    nonstandard_style,
+    rust_2024_compatibility
+)]
+#![warn(clippy::all, clippy::pedantic, clippy::cargo)]
+// List of denied lints from the clippy::restriction group.
+// https://rust-lang.github.io/rust-clippy/master/index.html#?groups=restriction
+#![warn(
+    clippy::undocumented_unsafe_blocks,
+    clippy::dbg_macro,
+    clippy::empty_enum_variants_with_brackets,
+    clippy::exit,
+    clippy::float_cmp_const,
+    clippy::lossy_float_literal,
+    clippy::macro_use_imports,
+    clippy::manual_ok_or,
+    // TODO: consider clippy::map_err_ignore
+    // TODO: consider clippy::mem_forget
+    clippy::rc_mutex,
+    clippy::rest_pat_in_fully_bound_structs,
+    clippy::string_add,
+    clippy::string_to_string,
+    clippy::todo,
+    // TODO: consider clippy::unimplemented
+    // TODO: consider clippy::unwrap_used
+)]
+// List of permanently allowed lints.
+#![allow(
+    // It's ok to cast u8 to bool, etc.
+    clippy::cast_lossless,
+)]
+// List of temporarily allowed lints.
+// TODO: Switch to except() once stable with 1.81.
+// TODO: fix code and reduce list or move to permanent list above.
+#![allow(
+    clippy::cargo_common_metadata,
+    clippy::cast_possible_truncation,
+    clippy::cast_possible_wrap,
+    clippy::cast_precision_loss,
+    clippy::cast_sign_loss,
+    clippy::default_trait_access,
+    clippy::doc_markdown,
+    clippy::explicit_iter_loop,
+    clippy::float_cmp,
+    clippy::if_not_else,
+    clippy::ignored_unit_patterns,
+    clippy::implicit_hasher,
+    clippy::inconsistent_struct_constructor,
+    clippy::inline_always,
+    clippy::items_after_statements,
+    clippy::manual_assert,
+    clippy::manual_let_else,
+    clippy::manual_string_new,
+    clippy::match_bool,
+    clippy::match_same_arms,
+    clippy::match_wild_err_arm,
+    clippy::missing_errors_doc,
+    clippy::missing_panics_doc,
+    clippy::module_name_repetitions,
+    clippy::multiple_crate_versions,
+    clippy::must_use_candidate,
+    clippy::needless_for_each,
+    clippy::needless_pass_by_value,
+    clippy::needless_raw_string_hashes,
+    clippy::option_as_ref_cloned,
+    clippy::redundant_closure_for_method_calls,
+    clippy::redundant_else,
+    clippy::return_self_not_must_use,
+    clippy::similar_names,
+    clippy::single_char_pattern,
+    clippy::single_match_else,
+    clippy::struct_excessive_bools,
+    clippy::struct_field_names,
+    clippy::too_many_lines,
+    clippy::uninlined_format_args,
+    clippy::unnested_or_patterns,
+    clippy::unreadable_literal,
+    clippy::unused_async,
+    clippy::unused_self,
+    clippy::used_underscore_binding,
+    clippy::wildcard_imports
+)]
+// List of temporarily allowed lints to unblock beta/nightly.
+#![allow(unknown_lints, clippy::manual_inspect)]
 
 use std::convert::Infallible;