deps: Add rand crate for randomized backoff and jitter

The embedding pipeline and retry queues need randomized exponential
backoff to prevent thundering herd effects when Ollama or GitLab
recover from transient failures. The rand crate (0.8) provides the
thread-safe RNG needed for jitter computation.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Cargo.lock

@@ -1093,6 +1093,7 @@ dependencies = [
  "futures",
  "indicatif",
  "open",
+ "rand",
  "reqwest",
  "rusqlite",
  "serde",
@@ -1339,6 +1340,15 @@ dependencies = [
  "zerovec",
 ]
 
+[[package]]
+name = "ppv-lite86"
+version = "0.2.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85eae3c4ed2f50dcfe72643da4befc30deadb458a9b590d720cde2f2b1e97da9"
+dependencies = [
+ "zerocopy",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.106"
@@ -1363,6 +1373,36 @@ version = "5.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
 
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom 0.2.17",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.5.18"
@@ -2553,6 +2593,26 @@ dependencies = [
  "synstructure",
 ]
 
+[[package]]
+name = "zerocopy"
+version = "0.8.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dafd85c832c1b68bbb4ec0c72c7f6f4fc5179627d2bc7c26b30e4c0cc11e76cc"
+dependencies = [
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.8.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7cb7e4e8436d9db52fbd6625dbf2f45243ab84994a72882ec8227b99e72b439a"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "zerofrom"
 version = "0.1.6"

Cargo.toml

@@ -40,6 +40,7 @@ thiserror = "2"
 dirs = "6"
 url = "2"
 urlencoding = "2"
+rand = "0.8"
 sha2 = "0.10"
 flate2 = "1"
 chrono = { version = "0.4", features = ["serde"] }