[V1.2.3] Actions update to follow the standard

[zfoong]

Rename actions:
find_file -> glob_search
grep_files -> grep_search
task_update_todos -> todos_write

Improve action function
grep_search -> add more parameters
Web_fetch -> add prompt for content normalization and summarization, and HTTP GET with auto-upgrade to HTTPS
send_message -> resolve attachment size, path. merge with send_message_with_attachment.
web_search -> deduplicates results and caps.

All acton outputs should be JSON-serialized via serde_json::to_string_pretty

Add new actions
action_search -> search action with query, return action name and its action set
skill_search -> find related skill from query, return skill name and description
skill_list -> list all enabled skills and its description
skill_add -> read skill into system prompt
config? -> stable way to self-configure for CraftBot