feat: collapse quoted reply text

[Shabhareash]

Detect quoted/reply blocks (styled in rounded-border boxes) and collapse them into a single '▶ quoted text hidden' indicator by default. Pressing 'q' (configurable via toggle_quotes keybind) expands/collapses the quoted sections.

Changes:

• view/html.go: add CollapseQuotedText() that identifies rendered quote boxes by their ╭/╰ border chars and replaces them with a one-line summary
• tui/email_view.go: add showQuotedText toggle, collapse quotes by default, re-render body on toggle; add 'q: toggle quotes' to help bar
• config: add toggle_quotes keybind (default: q) to EmailKeys

Closes #1598

What?

Why?

[floatpanebot]

Hi @Shabhareash! Please fix the following issues with your PR:

• Title: Is too long (54 characters). The PR title must be strictly under 40 characters.

[floatpanebot]

Benchmark report — no significant change

Metrics worse: 0 · better: 0 (threshold: ±3%).

benchstat output

goos: linux
goarch: amd64
pkg: github.com/floatpane/matcha/backend
cpu: AMD EPYC 7763 64-Core Processor                
                           │    old.txt    │               new.txt                │
                           │    sec/op     │    sec/op      vs base               │
ParseSearchQuery_Simple-4    3.772µ ± 304%   3.208µ ± 120%        ~ (p=0.310 n=6)
ParseSearchQuery_Complex-4   5.587µ ±  67%   9.161µ ±  41%        ~ (p=0.132 n=6)
TokenizeSearchQuery-4        5.280µ ±  41%   6.973µ ±  56%        ~ (p=0.485 n=6)
geomean                      4.810µ          5.895µ         +22.57%

                           │  old.txt   │              new.txt               │
                           │    B/op    │    B/op     vs base                │
ParseSearchQuery_Simple-4    26.00 ± 0%   26.00 ± 0%       ~ (p=1.000 n=6) ¹
ParseSearchQuery_Complex-4   762.0 ± 0%   762.0 ± 0%       ~ (p=1.000 n=6) ¹
TokenizeSearchQuery-4        176.0 ± 0%   176.0 ± 0%       ~ (p=1.000 n=6) ¹
geomean                      151.6        151.6       +0.00%
¹ all samples are equal

                           │  old.txt   │              new.txt               │
                           │ allocs/op  │ allocs/op   vs base                │
ParseSearchQuery_Simple-4    2.000 ± 0%   2.000 ± 0%       ~ (p=1.000 n=6) ¹
ParseSearchQuery_Complex-4   23.00 ± 0%   23.00 ± 0%       ~ (p=1.000 n=6) ¹
TokenizeSearchQuery-4        9.000 ± 0%   9.000 ± 0%       ~ (p=1.000 n=6) ¹
geomean                      7.453        7.453       +0.00%
¹ all samples are equal

pkg: github.com/floatpane/matcha/tui
                    │   old.txt    │               new.txt               │
                    │    sec/op    │    sec/op      vs base              │
LogPanelView-4        173.2µ ± 20%    161.8µ ±  8%  -6.58% (p=0.041 n=6)
SearchOverlayView-4   197.0µ ± 14%    175.7µ ±  7%       ~ (p=0.065 n=6)
InboxConstruction-4   997.7µ ± 17%   1030.1µ ± 33%       ~ (p=0.937 n=6)
geomean               324.1µ          308.3µ        -4.89%

                    │    old.txt    │               new.txt               │
                    │     B/op      │     B/op       vs base              │
LogPanelView-4        44.67Ki ± 51%   44.67Ki ± 51%       ~ (p=1.000 n=6)
SearchOverlayView-4   56.14Ki ± 41%   44.66Ki ± 26%       ~ (p=0.359 n=6)
InboxConstruction-4   874.3Ki ±  0%   874.3Ki ±  0%       ~ (p=0.734 n=6)
geomean               129.9Ki         120.4Ki        -7.34%

                    │   old.txt   │              new.txt              │
                    │  allocs/op  │  allocs/op   vs base              │
LogPanelView-4         714.0 ± 0%    714.0 ± 0%       ~ (p=1.000 n=6)
SearchOverlayView-4    926.0 ± 0%    925.0 ± 0%       ~ (p=0.545 n=6)
InboxConstruction-4   3.478k ± 0%   3.478k ± 0%       ~ (p=0.316 n=6)
geomean               1.320k        1.319k       -0.03%

_{auto-generated by benchmarks.yml}

Formatting issues have been resolved. Thank you!