chore(boundary): add metrics and access control to salt_sharing canister (dfinity#3762)

**Changes**:
- added metrics
- bazelification
- access control, only API boundary nodes can call the `get_salt()`
- `inspect_message` for early rejections of replicated query calls
- added polling of API boundary nodes
- improved structure by moving implementation of `/logs`

**How to test**:
```
// deploy with dfx
$ dfx deploy salt_sharing -m reinstall --playground --argument \          
    '(record {   
        regenerate_now = true;
        salt_generation_strategy = variant { StartOfMonth };
        registry_polling_interval_secs = 60;
    })'
```
**Check metrics**:
```
https://{canister_id}.raw.icp0.io/metrics
```
**Check logs**:
```
https://{canister_id}.raw.icp0.io/logs
```

---------

Co-authored-by: IDX GitLab Automation <[email protected]>
Co-authored-by: r-birkner <[email protected]>

Author: 3 people

Cargo.lock

@@ -0,0 +1,46 @@
+load("@rules_rust//rust:defs.bzl", "rust_test")
+load("//bazel:canisters.bzl", "rust_canister")
+
+package(default_visibility = ["//visibility:public"])
+
+DEPENDENCIES = [
+    # Keep sorted.
+    "//rs/boundary_node/salt_sharing/api:salt_sharing_api",
+    "//rs/nns/constants",
+    "//rs/rust_canisters/canister_log",
+    "//rs/rust_canisters/http_types",
+    "@crate_index//:candid",
+    "@crate_index//:ic-cdk",
+    "@crate_index//:ic-cdk-timers",
+    "@crate_index//:ic-stable-structures",
+    "@crate_index//:prometheus",
+    "@crate_index//:serde",
+    "@crate_index//:serde_cbor",
+    "@crate_index//:serde_json",
+    "@crate_index//:time",
+]
+
+MACRO_DEPENDENCIES = [
+    # Keep sorted.
+    "@crate_index//:ic-cdk-macros",
+]
+
+rust_canister(
+    name = "salt_sharing_canister",
+    srcs = glob(["canister/**/*.rs"]),
+    crate_name = "salt_sharing_canister",
+    crate_root = "canister/lib.rs",
+    proc_macro_deps = MACRO_DEPENDENCIES,
+    service_file = "canister/salt_sharing_canister.did",
+    deps = DEPENDENCIES,
+)
+
+rust_test(
+    name = "unit_tests",
+    srcs = glob(["canister/**/*.rs"]),
+    crate_name = "salt_sharing_canister",
+    crate_root = "canister/lib.rs",
+    data = ["canister/salt_sharing_canister.did"],
+    proc_macro_deps = MACRO_DEPENDENCIES,
+    deps = DEPENDENCIES + ["@crate_index//:candid_parser"],
+)

rs/boundary_node/salt_sharing/BUILD.bazel

@@ -1,5 +1,5 @@
 [package]
-name = "salt"
+name = "salt_sharing"
 version.workspace = true
 authors.workspace = true
 edition.workspace = true
@@ -13,14 +13,17 @@ ic-canister-log = { path = "../../rust_canisters/canister_log" }
 ic-cdk = { workspace = true }
 ic-cdk-macros = { workspace = true }
 ic-cdk-timers = { workspace = true }
+ic-nns-constants = { path = "../../nns/constants" }
 ic-stable-structures = { workspace = true }
-salt-api = { path = "./api" }
+prometheus = {workspace = true }
+salt-sharing-api = { path = "./api" }
 serde = { workspace = true }
 serde_cbor = { workspace = true }
 serde_json = { workspace = true }
 time = { workspace = true }
 
 [dev-dependencies]
+candid_parser = { workspace = true }
 
 [lib]
 crate-type = ["cdylib"]

rs/boundary_node/salt_sharing/Cargo.toml

@@ -0,0 +1,18 @@
+load("@rules_rust//rust:defs.bzl", "rust_library")
+
+package(default_visibility = ["//visibility:public"])
+
+DEPENDENCIES = [
+    # Keep sorted.
+    "@crate_index//:candid",
+    "@crate_index//:serde",
+]
+
+rust_library(
+    name = "salt_sharing_api",
+    srcs = glob(["src/**/*.rs"]),
+    aliases = {},
+    crate_name = "salt_sharing_api",
+    proc_macro_deps = [],
+    deps = DEPENDENCIES,
+)

rs/boundary_node/salt_sharing/api/BUILD.bazel

@@ -1,5 +1,5 @@
 [package]
-name = "salt-api"
+name = "salt-sharing-api"
 version.workspace = true
 authors.workspace = true
 edition.workspace = true

rs/boundary_node/salt_sharing/api/Cargo.toml

@@ -1,4 +1,5 @@
-use candid::{CandidType, Deserialize};
+use candid::{CandidType, Principal};
+use serde::{Deserialize, Serialize};
 
 pub type GetSaltResponse = Result<SaltResponse, GetSaltError>;
 
@@ -26,3 +27,11 @@ pub enum GetSaltError {
     Unauthorized,
     Internal(String),
 }
+
+#[derive(CandidType, Serialize, Deserialize, Clone, PartialEq, Debug, Eq)]
+pub struct ApiBoundaryNodeIdRecord {
+    pub id: Option<Principal>,
+}
+
+#[derive(CandidType, Deserialize, Clone, Copy, PartialEq, Eq)]
+pub struct GetApiBoundaryNodeIdsRequest {}