store history using sqlite, add suggestion with open

README.md

@@ -67,6 +67,11 @@ Like qutebrowser, keys mean different things depending on the mode:
 The command line keeps a history (`Up`/`Down`) and aborts on `Escape`, `Ctrl-c`,
 or if you delete the leading `:`.
 
+While typing `:open` (or `:o`), a completion list of previously visited pages
+appears above it, most recent first. Every word you type must appear in the URL
+or the title. `Tab` / `Shift-Tab` cycle through the list and put the selected URL
+on the command line; `Enter` opens it.
+
 ## Hint mode
 
 `f` labels every clickable element in the viewport with home-row letters
@@ -82,7 +87,12 @@ shadow DOM yet.
 
 ## Browsing data
 
-Cookies, local storage and history are kept in a persistent QtWebEngine profile
+Browsing history is kept in `~/.local/share/att/att/history.sqlite` (tables
+`visits`, one row per page load, and `urls`, one row per URL for completion).
+A page is recorded once it finishes loading, so redirect hops and in-page
+`#anchor` jumps don't create entries. `:history-clear` empties it.
+
+Cookies, local storage and Chromium's own state are kept in a persistent QtWebEngine profile
 under `~/.local/share/att/att/QtWebEngine/default` (the cache is in
 `~/.cache/att/att/`). Session cookies are saved too, like qutebrowser's
 `content.cookies.store`, so you stay logged in across restarts. Delete that
@@ -104,7 +114,7 @@ on, for when a site breaks.
 ## Commands
 
 `:open <url|query>` (alias `:o`), `:quit` (alias `:q`), `:reload`, `:back`,
-`:forward`, `:stop`, `:adblock-update`, `:adblock-toggle`.
+`:forward`, `:stop`, `:history-clear`, `:adblock-update`, `:adblock-toggle`.
 
 `:open` accepts a full URL, a bare host (`example.com` → `https://example.com`),
 an existing local path, or free text, which goes to DuckDuckGo.
@@ -118,6 +128,8 @@ an existing local path, or free text, which goes to DuckDuckGo.
 | `src/main.cpp`      | `QApplication`, CLI parsing, stylesheet                 |
 | `src/browserwindow` | the window, mode state machine, key dispatch, commands  |
 | `src/commandline`   | the `:` prompt                                          |
+| `src/history`       | SQLite browsing history                                 |
+| `src/completionview`| the `:open` completion list                             |
 | `src/statusbar`     | mode / URL / progress line                              |
 | `src/adblock`       | request interceptor around the adblock engine           |
 | `adblock/`          | Rust crate: C API over adblock-rust, built by Corrosion |