feat(io): Add Streaming File Input Component

config/examples/streaming_file_tail.yaml

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+# Streaming File Input Example
+# ============================
+# This example demonstrates using streaming_file to tail a log file,
+# similar to 'tail -F' but with automatic rotation and truncation handling.
+#
+# Quick Test:
+#   1. Create a test file:
+#      echo "hello world" > /tmp/test.log
+#
+#   2. Run bento:
+#      bento -c config/examples/streaming_file_tail.yaml
+#
+#   3. In another terminal, append lines:
+#      echo "new line 1" >> /tmp/test.log
+#      echo "new line 2" >> /tmp/test.log
+#
+# Performance Note:
+#   By default, polling-only mode is used (disable_fsnotify: true) which is
+#   more CPU-efficient for high-volume log files. For lower latency on
+#   low-volume files, set disable_fsnotify: false.
+
+input:
+  streaming_file:
+    path: /tmp/test.log
+    poll_interval: 200ms      # How often to check for new data
+    disable_fsnotify: true    # true = polling only (CPU efficient)
+                              # false = use fsnotify (lower latency)
+
+pipeline:
+  processors:
+    - mapping: |
+        # Add timestamp to each line
+        root.timestamp = now()
+        root.content = content().string()
+        root.metadata = @
+
+output:
+  stdout:
+    codec: lines

internal/impl/io/inode_other.go

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+//go:build !unix
+
+package io
+
+import "os"
+
+// inodeOf extracts the inode from a FileInfo on non-Unix systems
+// On Windows and other non-Unix systems, inodes are not available
+// Returns (0, false) to indicate inode support is not available
+// Rotation detection will fall back to size-based heuristics
+func inodeOf(_ os.FileInfo) (uint64, bool) {
+	return 0, false
+}

internal/impl/io/inode_unix.go

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+//go:build unix
+
+package io
+
+import (
+	"os"
+	"syscall"
+)
+
+// inodeOf extracts the inode from a FileInfo on Unix-like systems
+// Returns (inode, true) if inode is available, (0, false) otherwise
+func inodeOf(fi os.FileInfo) (uint64, bool) {
+	if st, ok := fi.Sys().(*syscall.Stat_t); ok {
+		return st.Ino, true
+	}
+	return 0, false
+}