Write debug logs on disk if `--log-output-path` is specified.

Log files are rotated automatically once the file size reaches 50MB.

Rotated log files will be kept for 7 days - max 10 rotated files will be kept, whatever comes first.

category: feature
ticket: #2671

(dependabot) Bumps [golang.org/x/time](https://github.com/golang/time) from 0.4.0 to 0.5.0.

Adds a check for activation epoch to filter active validators before resolving duties.

category: bug
ticket: #2721

(dependabot) Bumps [golang.org/x/tools](https://github.com/golang/tools) from 0.15.0 to 0.16.0.

Adds custom testnet flags to `charon create cluster` and `charon run` commands.

category: feature
ticket: #2690

Removes feature flags from feature set with stable status.

category: misc
ticket: #2720

As part of recent go-eth2-client upgrade, `ProposerDuties` and `AttesterDuties` calls started to return Metadata fields: 
```
  "dependent_root": "0xc01a8003a974cea31fd9e91c7d2cec8120ea3cc71edcbb836b6fbede6c289a69",
  "execution_optimistic": false,
```

This change updates the corresponding handlers of validator API to properly parse and propagate these new fields. 

category: feature
ticket: #2736

The previous build failed due to older go version (1.21.4), now bumped to 1.21.5.

category: fixbuild
ticket: none

go-eth2-client handles `dependent_root` metadata as a special case and produces a `Root` object rather than hex string.
  
https://github.com/attestantio/go-eth2-client/blob/a05485e0e75749f2b6912db2972a35ec2ec37c3b/http/json.go#L32C25-L32C25

category: bug
ticket: #2736

(dependabot) Bumps [github.com/spf13/viper](https://github.com/spf13/viper) from 1.17.0 to 1.18.1.