Add Profiling Support for Indexer/tap-agent services (#704)

* feat(docker): Add continuous profiling with embedded pprof and external tools

- Embedded continuous profiling using pprof in Rust code
- External tools: flamegraph, valgrind, callgrind, strace
- Docker support for all profiling methods
- Just commands for easy profiling management

Flamegraphs and profiles are saved to contrib/profiling/output.

* feat(indexer): Integrate pprof tool into service binary

* feat(gitignore): Ignore profiling files

* feat(profiling): Integrate profiling into tap-agent service

* feat(profiling): Integrate pprof into tap-agent binary

* refactor(profiling): extract profiling into dedicated crate

Move duplicated profiling functionality from multiple crates into a single
shared 'profiler' crate.

Key changes:
- Create new 'profiler' crate with optimized implementation
- Use AtomicU64 instead of Mutex for snapshot counter
- Add proper error handling with thiserror
- Ensure proper directory structure for profiling output
- Make profiling opt-in via a feature flag

* fix(profiler): Add missing script to setup profiling

* fix(docker): Fix base image for profiling

* fix(justfile): Add tap-agent

* chore(cargo): Add debug symbols comment

* chore(cargo): Add comment to enable debug symbols

* feat(profiler): Use human readable date/time

* feat(profiler): Enable other callgrind options

* chore(code): Some cleanups

* feat(profiler): Add profiling instructions

* fix(profiler): Fix doctest documentation in profiler

* fix(test): Disable profiling in cargo test

Author: neithanmo

.gitignore

@@ -17,6 +17,8 @@ crates/dips/node_modules/
 crates/dips/generated/
 crates/dips/npm-debug.log*
 contrib/local-network
+contrib/profiling/indexer-service
+contrib/profiling/tap-agent
 node_modules
 target/
 *.code-workspace

Cargo.lock

@@ -6,6 +6,7 @@ members = [
     "crates/dips",
     "crates/indexer-receipt",
     "crates/monitor",
+    "crates/profiler",
     "crates/query",
     "crates/service",
     "crates/tap-agent",
@@ -15,6 +16,13 @@ members = [
 ]
 resolver = "2"
 
+# This is to enable debug symbols
+# which are useful during profiling 
+# with callgrind
+# [profile.release]
+# debug = true
+# force-frame-pointers = true
+
 [profile.dev.package."*"]
 opt-level = 3