docs(obsidian-cli): drop silent flag; document output option placement

[arimu1]

Summary

Updates skills/obsidian-cli/SKILL.md so agents follow current Obsidian CLI behavior (verified against https://obsidian.md/help/cli and issue #129 report on 1.12.7).

Changes

1. Remove silent — the flag no longer exists. Creating/appending no longer opens notes by default; opening is opt-in via open / newtab. Unknown flags are ignored, so stale silent advice fails quietly.
2. Document placement of --copy / --json / --md / --tsv / --csv — these only work after the command name. Putting them before the command (or before vault=) is misparsed as the command (Command "--copy" not found). Examples show correct vs incorrect order; note that many list commands also accept format=json|tsv|csv.

Related

• Pre-existing open PR docs(obsidian-cli): sync with current CLI behavior #78 also touches silent/default open behavior as part of a broader CLI docs sync, but does not document output-option placement (the second half of obsidian-cli: silent flag no longer exists, and --copy/--json only work after the command #129). This PR is scoped strictly to obsidian-cli: silent flag no longer exists, and --copy/--json only work after the command #129.

Test plan

• Cross-checked official CLI docs: create uses open / overwrite / newtab (no silent)
• Cross-checked official docs: --copy examples place the flag after the command (read --copy)
• Confirmed no open PR already linked to obsidian-cli: silent flag no longer exists, and --copy/--json only work after the command #129
• Maintainer: optional smoke with live CLI (obsidian create ... silent no-op; obsidian --copy … errors; post-command --copy works)

AI disclosure

Docs-only change; AI-assisted drafting (Grok implementator) with human review via arimu1.

Fixes #129

[guojunyuan2004]

Independently reproduced on Obsidian 1.13.7 (installer 1.13.7) on macOS, using the same repo state (main @ a1dc48e):

• obsidian help create lists only overwrite, open, newtab — no silent. So removing it is correct, and the opt-in-open wording is more accurate.
• --copy before the command fails exactly as described in obsidian-cli: silent flag no longer exists, and --copy/--json only work after the command #129:
  • obsidian --copy vaults → Error: Command "--copy" not found. It may require a plugin to be enabled.
  • after the command it works and the clipboard receives the output:
    • obsidian vaults --copy → clipboard contains Note
    • obsidian read file="CLAUDE" --copy → clipboard contains the file body.

Both fixes in this PR are what agents need. The current silent advice is a particularly easy-to-miss failure mode: unknown flags are ignored, so the command exits 0 and the agent believes the note opened as intended when it didn't. Thanks for scoping it strictly to #129 — that makes review easy.