fix(telescope): guard layout_config width and improve picker sizing
- Prevent nil index error when
`config.layout_config[config.layout_strategy]`
 is not defined (common on newer Telescope versions).
- Resolve picker width using a safe precedence chain:
 telescope_opts.width → telescope_opts.layout_config.width →
config.width →
 config.layout_config.width → per-strategy width → fallback 0.8.
- Clamp absolute widths to terminal width to prevent overflow.
- Derive column widths from actual picker width instead of vim.o.columns
for
 better alignment.
- Guard against missing entry fields (tags, section, description,
cheatcode)
 to avoid crashes on malformed entries.
References:
- Telescope deprecation of config.width:
nvim-telescope/telescope.nvim@5a53ec5
- Layout config refactor:
 nvim-telescope/telescope.nvim#1039