cli: add --narrow option to user list

[ben-dz]

Summary of Changes

• Add --narrow flag to doublezero user list that produces a terminal-friendly table by dropping location, cyoa_type, accesspass, and tunnel_net, abbreviating user_type (e.g. IBRLWithAllocatedIP → IBRL+IP), and summarizing groups as one P: entry and one S: entry, each followed by +N for remaining groups of that role.
• Leave the default (non-narrow) table and JSON output unchanged — no changes to column set, column widths, or string formatting on the existing paths.
• Narrow rows fit under a 240-column budget for typical mainnet data; a render-level test enforces that cap on every line of narrow output.

Diff Breakdown

Category	Files	Lines (+/-)	Net
Core logic	1	+105 / -0	+105
Tests	1	+115 / -0	+115
Docs	1	+3 / -0	+3
Total	2	+223 / -0	+223

Change is additive only: one new CLI flag plus a dedicated narrow-render struct and helpers, alongside direct unit tests for the group summarizer and an end-to-end --narrow execution test.

Key files (click to expand)

• smartcontract/cli/src/user/list.rs — adds --narrow arg, UserDisplayNarrow (11-column Tabled struct), abbreviate_name / abbreviate_user_type / narrow_groups / narrow_role_entry helpers, new unit test for narrow_groups, and a --narrow case in test_cli_user_list that also asserts every rendered row fits in 240 columns.
• CHANGELOG.md — entry under Unreleased → Changes → CLI describing the new flag and confirming default output is unchanged.

Testing Verification

• cargo test -p doublezero_cli --lib user::list:: passes (13 tests), including the new narrow_groups unit test (empty, single-role, overflow, dual-role with independent +N) and the --narrow execution test that checks header membership, hidden columns, and the 240-col row cap.
• cargo clippy -p doublezero_cli --all-targets -- -Dclippy::all -Dwarnings is clean.
• cargo +nightly fmt -p doublezero_cli --check is clean.
• Manually verified the mainnet widest-row sample (6 subscriber groups, Prepaid MAX accesspass) renders as ~238 chars in narrow mode with S:edge..reds+5 in the groups column.